JP5482838B2 - Communication device - Google Patents

Description

  The present invention relates to a communication apparatus for transferring a frame, and more particularly to a communication apparatus for transferring a frame using a logical link configured by integrating a plurality of physical links.

  When data is transmitted to a communication partner terminal device via a network, the transmission data is divided into frames in the data link layer, relayed by the communication device, and delivered to the communication partner. A communication device that relays frames includes a layer 2 switch. Here, as a method of improving the quality of a communication path between communication apparatuses, a technique of link aggregation (Link Aggregation: LAG) is known. Link aggregation is a technology in which a plurality of physical links such as cables are installed between the same communication devices, and these physical links are bundled to form one virtual logical link, and is defined in IEEE 802.3ad. ing.

  By performing link aggregation and increasing the transmission band, a high-speed communication path can be realized without preparing an expensive cable or communication interface. In recent years, link aggregation has been increasingly used for the purpose of link redundancy in carrier networks provided by communication carriers. This is because multiple physical links are used simultaneously by link aggregation, so even if some of the physical links fail, it is possible to prevent the communication path from being completely disconnected and improve availability. is there.

  For example, among the physical links constituting the logical link, a predetermined link is used as a working link, and links other than the working link are pseudo-blocked to be used as backup links. The working link in this logical link is used as a working link for communication, and the status of the working link is monitored. When some of the operation links become unavailable, the part of the operation links are detached from the link aggregation group, the pseudo link of the protection link is released, and the protection link is changed to the link aggregation group. A technique for attaching as an operation link is also known (see, for example, Patent Document 1). In this technique, among links constituting a logical link, one link group is used as a working link, and the other group is used as a backup link. When a failure occurs on the working link, the working link is changed to the unused state and the spare link is changed from the unused state to the usable state. Thus, network connection by link aggregation is enabled.

JP 2004-349664 A

  Here, even in a network that transfers frames using the link aggregation function, a down due to the occurrence of a failure leads to a decrease in communication quality and a decrease in system availability. desirable. In particular, in carrier networks provided by telecommunications carriers that use the link aggregation function for link redundancy, it is required that switching to a normal link be completed as soon as possible and the connection is restored when a failure occurs. Has been.

  The present invention has been made in view of the above points, and is a communication device capable of high-speed switching from a working link to a backup link when a failure occurs in a working link in a communication network having a redundant configuration by link aggregation. The purpose is to provide.

According to one embodiment, in a communication apparatus that transfers a frame using a logical link configured by aggregating a plurality of physical links, an input means for inputting a frame, a case where an active logical link is used, and an active First storage means for storing aggregated multicast destination management information in which identification information of a plurality of physical link patterns for outputting a frame is associated with each other when a spare logical link is used instead of a logical link; of the physical links do not constitute a physical link and logical link constitutes a second storage means for storing a multicast address management information showing correspondence between identification information of the physical links and patterns frame is output, is input Aggregated multicast destination management information depending on whether the current logical link can be used for the frame It acquires identification information of one of the patterns, with reference to the multicast address management information, among the physical links do not constitute a physical link and logical link constituting the logical link, a physical link corresponding to the acquired pattern identification information And a multicast distribution means for determining a physical link for outputting a frame as a physical link.

  According to the disclosed communication device, when a failure occurs in a working link in a communication network using a logical link having a redundant configuration by link aggregation, high-speed switching from the working link to the backup link can be realized.

It is a figure which shows the outline | summary of this Embodiment. It is a figure which shows the whole structure of a frame transfer system. It is a figure which shows the hardware constitutions of a switch. It is a figure which shows the data structure example of a frame. It is a block diagram which shows the function of the switch of 1st Embodiment. FIG. 3 illustrates an example data structure of a flow destination management table according to the first embodiment. 6 is a diagram illustrating an example of a data structure of an aggregation management table according to the first embodiment. FIG. 6 is a diagram illustrating an example of a data structure of an aggregate destination management table according to the first embodiment. FIG. It is a figure which shows the example of a data structure of the aggregation destination management table in the modification of 1st Embodiment. It is a block diagram which shows the function of the distribution part of 2nd Embodiment. It is a figure which shows the example of a data structure of the aggregation destination statistics table of 2nd Embodiment. It is a block diagram which shows the function of the distribution part of 3rd Embodiment. It is a block diagram which shows the function of the switch of 4th Embodiment. It is a figure which shows the example of a data structure of the aggregation management table of 4th Embodiment. It is a figure which shows the example of a data structure of the aggregation destination management table of 4th Embodiment. It is a figure which shows the example of a data structure of the aggregation destination management table in the modification of 4th Embodiment. It is a block diagram which shows the function of the distribution part of 5th Embodiment. It is a figure which shows the example of a data structure of the aggregation destination statistics table of 5th Embodiment. It is a block diagram which shows the function of the switch of 6th Embodiment. It is a figure which shows the example of a data structure of the flow destination management table of 6th Embodiment. It is a figure which shows the example of a data structure of the aggregation multicast management table of 6th Embodiment. It is a figure which shows the example of a data structure of the aggregation multicast destination management table of 6th Embodiment. It is a figure which shows the example of a data structure of the multicast destination management table of 6th Embodiment.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing an outline of the present embodiment. As shown in FIG. 1, the communication apparatus 1 according to the present embodiment is a communication apparatus that transfers a frame using a logical link configured by aggregating a plurality of physical links, and has a redundant configuration by link aggregation. The link of the communication network is switched from the working link to the backup link based on the switching instruction.

  A communication apparatus 1 shown in FIG. 1 is an apparatus that transfers a frame to another communication apparatus or the like using a logical link configured by integrating a plurality of physical links. The communication device 1 includes an input unit 11, an aggregated destination management information storage unit 12, a distribution unit 13, a first output unit 14, and a second output unit 15 to transfer a frame using a logical link. ing.

The input unit 11 receives a frame transferred by the communication device 1 to another communication device, an information device such as a computer, or the like.
The aggregate destination management information storage unit 12 stores aggregate destination management information indicating a physical link to which a frame is output. Here, the aggregated destination management information constitutes an aggregated destination management table 12a and is stored in the aggregated destination management information storage unit 12. The physical link is each port (such as port # 0) included in the first output unit 14 and the second output unit 15.

  The aggregate destination management information includes the first physical link information (the left column of the aggregate destination management table 12a in the figure) for specifying the physical link of the first output means 14 and the physical link of the second output means 15. Second physical link information to be identified (the column on the right side of the aggregated destination management table 12a in the figure).

  The allocating unit 13 refers to the aggregate destination management information stored as the aggregate destination management table 12a in the aggregate destination management information storage unit 12, and logically links the physical link to which the frame input by the input unit 11 is output. The physical link is determined as one of the physical links constituting the link.

  Here, according to the switching instruction, the allocating unit 13 refers to the first physical link information, and determines the physical link from which the frame is output as the physical link constituting the first output unit 14. And the second state in which the physical link from which the frame is output with reference to the second physical link information is determined as the physical link constituting the second output means 15 can be switched. This switching instruction is used, for example, to detect the occurrence of a failure and the function of detecting the occurrence of a failure in the communication device 1 itself when a failure occurs in communication via a logical link between the communication device 1 and another communication device. A function of giving a switching instruction based on this may be provided. Note that a device other than the communication device 1 may have a function of detecting the occurrence of a failure and outputting a switching instruction.

  The first output means 14 is composed of some physical links of the physical links that make up the logical link. The second output unit 15 includes a part or all of the physical links other than the physical links configuring the first output unit 14 among the physical links configuring the logical link. .

  According to such a communication apparatus 1, a frame is input by the input unit 11, and aggregated destination management information indicating a physical link to which the frame is output is stored by the aggregated destination management information storage unit 12. The distribution unit 13 refers to the aggregated destination management information, and determines the physical link from which the frame is output as one of the physical links constituting the logical link. The first output means 14 is composed of a part of physical links constituting the logical link, and the second output means 15 is the first of the physical links constituting the logical link. It is composed of a part or all of the physical links other than the physical links constituting the output means 14. The aggregated destination management information includes first physical link information for specifying the physical link of the first output unit 14 and second physical link information for specifying the physical link of the second output unit 15. ing. A first state in which a physical link from which a frame is output with reference to the first physical link information by the allocating unit 13 is determined as a physical link constituting the first output unit 14, and a second physical link The physical link on which the frame information is output with reference to the link information can be switched to the second state determined as the physical link constituting the second output means 15, and the first state is determined according to the switching instruction. The state is switched to the second state.

  As a result, when a failure occurs in the working link in a communication network using a logical link having a redundant configuration by link aggregation, high-speed switching from the working link to the backup link can be realized.

[First Embodiment]
FIG. 2 is a diagram illustrating the overall configuration of the frame transfer system. In the frame transfer system of this embodiment, a plurality of layer 2 switches relay data link layer frames so that data can be transmitted and received between terminal devices.

  The frame transfer system shown in FIG. 2 includes switches 100, 100a, 100b, 100c, and 100d and terminal devices 40, 61, 62, 63, 64, 65, and 66. The switches 100, 100a, 100b, 100c, and 100d are layer 2 switches. The terminal devices 61, 62, 63, 64, 65, 66 are terminal devices used by the user. The terminal device 40 is a terminal device used by an administrator of the switch 100. The switches 100a, 100b, 100c, and 100d are configured in the same manner as the switch 100, and have equivalent functions.

  The switch 100 is connected to the switches 100a and 100b. The switch 100b is connected to the switches 100c and 100d. The terminal devices 61 and 62 are connected to the switch 100a. The terminal devices 63 and 64 are connected to the switch 100c. The terminal devices 65 and 66 are connected to the switch 100d. The terminal device 40 is connected to the switch 100. The two switches or the switch and the terminal device are connected by one or more physical links (network cables).

  The switches 100, 100a, 100b, 100c, and 100d relay the frame from the source terminal device to the destination terminal device according to the address included in the frame. For example, when the terminal device 61 transmits a frame to the terminal device 63, the frame is relayed in the order of the switch 100a, the switch 100, the switch 100b, and the switch 100c.

  FIG. 3 is a diagram illustrating a hardware configuration of the switch. FIG. 3 shows the internal configuration of the switch 100, but the switches 100a, 100b, 100c, and 100d can be realized with the same configuration. The switch 100 includes a CPU 101, interface cards 102a, 102b, 102c, and 102d, a switch card 103, a table storage memory 104, a port monitoring unit 105, and a bus 106.

  A CPU (Central Processing Unit) 101 controls the entire switch 100. The CPU 101 executes processing by a program. The CPU 101 executes a program similarly held in the memory using data held in a memory (not shown). The CPU 101 receives a command transmitted from the terminal device 40 used by the administrator via a communication interface (not shown), and returns an execution result for the command to the terminal device 40.

  The table storage memory 104 stores a plurality of tables. The table stored in the table storage memory 104 includes a table for managing the configuration of the logical link, a table for determining a frame transfer destination within the logical link, and a table for storing information indicating the frame transfer destination. It is.

  A CPU 101, interface cards 102a, 102b, 102c, and 102d, a switch card 103, a table storage memory 104, and a port monitoring unit 105 are connected to the bus 106.

  Each of the interface cards 102a, 102b, 102c, and 102d has a plurality of (for example, eight) communication ports. One physical link can be connected to each communication port. The interface cards 102a, 102b, 102c, and 102d monitor the respective communication ports and acquire frames. Note that the interface cards 102a, 102b, 102c, and 102d have a buffer that temporarily holds frames in preparation for the case where frames arrive at a plurality of communication ports at the same time. Then, the interface cards 102a, 102b, 102c, and 102d send the acquired frame to the switch card 103.

  The switch card 103 has a learning table (not shown). The switch card 103 stores the transmission source address of the frame received in the past and the identification information of the communication port or logical link from which the frame has arrived in association with each other in the learning table. This learning table is updated by the switch card 103 as needed.

  When the switch card 103 receives a frame from any one of the interface cards 102a, 102b, 102c, and 102d, the switch card 103 refers to the learning table and determines a transfer destination of the frame. Here, when the determined transfer destination is a logical link, the switch card 103 refers to the table stored in the table storage memory 104, and the specific interface cards 102a, 102b, 102c, 102d used for transfer and Determine the communication port. Thereafter, the switch card 103 sends the frame to the determined interface cards 102a, 102b, 102c, and 102d.

The interface cards 102a, 102b, 102c, and 102d that have received the frame send the received frame from the determined communication port to the transmission destination.
The port monitoring unit 105 monitors the communication ports of the interface cards 102a, 102b, 102c, and 102d. When the port monitoring unit 105 detects a failure or recovery of the physical link connected to the communication ports of the interface cards 102a, 102b, 102c, and 102d, the port monitoring unit 105 notifies the CPU 101 accordingly.

  FIG. 4 is a diagram illustrating an example of a data structure of a frame. The frame 30 shown in FIG. 4 is transmitted / received to / from the switches 100a, 100b, etc. via the communication ports of the interface cards 102a, 102b, 102c, 102d. The frame 30 includes a destination MAC address (MAC DA: Media Access Control address Destination Address), a source MAC address, a TPID (Tag Protocol Identifier), a VLAN (Virtual Local Area Network) tag, a type, a payload, and an FCS. (Frame Check Sequence).

  The destination MAC address is an address that uniquely identifies the communication interface of the destination terminal device. The transmission source MAC address is an address that uniquely identifies a communication interface of the transmission source terminal device. The TPID is a value indicating the type of the frame (for example, whether it is a VLAN frame or a normal frame). The VLAN tag is a uniquely determined value assigned to each logical network when one network is divided into a plurality of logical networks for operation. The type is a field that specifies a protocol to be used. The payload is a data body to be transmitted / received. For example, the payload is obtained by dividing an IP packet into a predetermined data length. FCS is a value used to detect an error in a received frame.

  It should be noted that the data structure of the frame can be variously modified according to the network operation mode and the like. For example, the VLAN tag may be omitted. Also, header information other than that shown in FIG. 4 may be added.

  FIG. 5 is a block diagram illustrating functions of the switch according to the first embodiment. 5 shows the module configuration of the switch 100, the other switches 100a, 100b, 100c, and 100d can be realized by the same module configuration as the switch 100.

  The switch 100 according to the present embodiment includes an input unit 110, a distribution unit 120, and a failure detection unit 130 in order to switch a link of a communication network having a redundant configuration by link aggregation from a working link to a backup link based on a switching instruction. A communication unit 140, a flow destination management information storage unit 151, an aggregate management information storage unit 152, an aggregate destination management information storage unit 153, an active system output unit 181, and a standby system output unit 182. The distribution unit 120 includes a flow destination determination unit 121, a switching determination unit 122, a hash calculation unit 123, a distribution destination determination unit 124, and a frame discard unit 125.

  Here, the active output unit is an output unit set as an output unit of the operation system in the initial state and the normal state. The standby system output unit is an output unit set as the standby system output unit in the initial state and the normal state.

  The input unit 110 receives a frame transferred by the switch 100 according to the present embodiment to other switches 100a, 100b, 100c, and 100d and a communication device such as a terminal device.

  The allocating unit 120 refers to the aggregated destination management information stored in the aggregated destination management information storage unit 153 as the aggregated destination management table 153a, and determines the physical link to which the frame input by the input unit 110 is output as a logical link. The physical link is determined as one of the physical links constituting the link.

  Here, in response to the switching instruction, the allocating unit 120 refers to the working physical link information and determines the physical link from which the frame is output as the physical link constituting the working output unit 181; The physical link from which the frame is output with reference to the standby system physical link information can be switched to the standby state in which the physical link constituting the standby system output unit 182 is determined.

  In the switching instruction, when a failure occurs in communication between the switch 100 and another switch through the logical link, the failure detection unit 130 detects the occurrence of the failure. Then, the failure detection unit 130 outputs a switching instruction to the switching determination unit 122 of the distribution unit 120 based on the detection of the occurrence of the failure. Based on the switching by the allocating unit 120, the active output unit 181 outputs a frame from the physical link that configures the active output unit 181, or the standby output unit 182 includes the physical that configures the standby output unit 182. Output frame from link.

  The distribution unit 120 switches from the active state to the standby state based on the number of usable physical links. The allocating unit 120 switches from the active state to the standby state when the number of physical links indicated by the valid physical link information of the active output unit 181 is less than the band indicated by the band information. Band information indicating a band to be secured for transmitting the frame is set in the frame transmitted by the switch 100 according to the transmission destination. This band information is stored in a storage unit (not shown) included in the switch 100.

  The flow destination determination unit 121 refers to the flow destination management information stored in the flow destination management information storage unit 151, configures a physical link from which a frame is output, a physical link that constitutes a logical link, or a logical link One of the physical links (not shown) other than the physical link to be determined is determined.

  The flow destination determination unit 121 specifies the destination of each frame using the flow destination management table 151a described later in FIG. 6 based on the input destination MAC address (see FIG. 4) of the frame. That is, the flow destination determination unit 121 extracts the MAC address included in the input frame. At this time, the MAC address of the input frame is associated with the address of the destination field in which the destination of the frame is stored by the flow destination management table 151a. Using this, the switch 100 acquires the destination stored in the corresponding address of the flow destination management table 151a from the MAC address of the input frame.

  Also, when the destination port is a logical link (LAG), by setting 1 in the L field associated with the destination MAC address of the frame transmitted on the logical link in the flow destination management table 151a, the logical destination is set. A link can be specified. Accordingly, when 1 is set in the L field associated with the destination MAC address of the frame, the flow destination determination unit 121 determines the destination of the frame as the designated logical link.

  The information on the frame side to be associated with the address of the flow destination management table 151a is not limited to the destination MAC address, and a value indicated by the VLAN tag (see FIG. 4) may be used.

  Further, when the destination MAC address or the VLAN tag is used for association with the address of the flow destination management table 151a, the number of bits of the address on the flow destination management table 151a side becomes very large. Based on this, the memory capacity required for the flow destination management table 151a increases. On the other hand, a CAM (Content Addressing Memory) may be used instead of a general SRAM (Static Random Access Memory) and DRAM (Dainamic Random Access Memory) as a memory for storing the flow destination management table 151a. Thereby, it is not necessary to directly use the destination MAC address or VLAN tag as the address of the flow destination management table 151a, and the destination MAC address or VLAN tag can be used as search information (search key). As a result, there is no need to have a memory capacity table corresponding to the number of bits on the flow destination management table 151a side, and the memory for storing the flow destination management table 151a can be saved.

  When the switching determination unit 122 detects a switching instruction from the failure detection unit 130, the switching determination unit 122 rewrites the aggregate management information from indicating the current status to indicating the standby status. Based on this, the distribution destination determination unit 124 that refers to the aggregation management information determines the physical link from which the frame is output from the active output unit 181 and the standby output unit 182.

  Further, the switching determination unit 122 refers to the aggregation management information and causes the hash calculation unit 123 to perform hash calculation. At this time, the switching determination unit 122 extracts frame part information from the entire frame based on the frame part specifying information, and causes the hash calculation unit 123 to perform hash calculation using the extracted frame part information. Further, the switching determination unit 122 causes the hash calculation unit 123 to perform hash calculation based on the calculation content information. Further, when detecting the operation non-execution information, the switching determination unit 122 determines a physical link that outputs a frame without causing the hash calculation unit 123 to perform hash calculation.

  Here, the frame part information is information constituting a part of the frame, and for example, an address included in the frame can be used. The address used as the frame partial information is information for specifying a frame transmission source terminal device (or a set to which the transmission source terminal device belongs) and a destination terminal device (or a set to which the destination terminal device belongs). . For example, a source / destination MAC address, a source / destination IP (Internet Protocol) address, a VLAN tag, and the like. The frame portion specifying information specifies the position and range of the frame portion information in the frame.

  In this embodiment, in order to associate the address, which is the frame part information, with the physical link, for example, the hash value calculated from the address and the port number of the communication port to which the physical link is connected have a one-to-one correspondence. Use with attachment.

  The hash calculation unit 123 uses a hash function that can take the same number of types of values as the number of physical links included in the active output unit 181 and the standby output unit 182 as frame part information constituting a part of the frame. Calculate the hash value.

  Here, in the hash calculation, the frame part information specified by the frame part specifying information of the frame to be transmitted is converted into the number of ports that can be used at that time of the logical link that transmits the frame (the maximum value is N, for example, 8 ) And the remainder of the result of division (0 to N-1, for example, 0 to 7) is used. Further, depending on the setting, a value obtained by dividing the frame partial information of the frame to be transmitted by the generator polynomial can be used.

  The distribution destination determination unit 124 determines a physical port to which a frame is output based on the determination by the flow destination determination unit 121. The distribution destination determination unit 124 refers to the aggregate management information to switch from the active state to the standby state, and refers to the aggregate destination management information, based on the hash value obtained by the hash calculation unit 123 calculating. The physical link to which the frame is output is determined.

  The frame discard unit 125 discards the frame when the frame discard information included in the aggregate destination management information indicates that the frame is to be discarded. Thereby, when performing a test about the operation of the switch 100 and the connection destination, it is possible to limit the frames to be output when the frame is transmitted only to a specific transmission destination or only to a specific transmission destination.

The failure detection unit 130 detects the occurrence of a failure in the physical link constituting the active output unit 181 and outputs a switching instruction when the occurrence of the failure is detected.
The flow destination management information storage unit 151 is a flow destination management information indicating whether a physical link from which a frame is output is a physical link constituting a logical link or a physical link other than a physical link constituting a logical link. Remember.

  The aggregation management information storage unit 152 stores aggregation management information indicating whether a frame is output from a physical link configuring the active system output unit 181 or from a physical link configuring the standby system output unit 182.

  Further, the aggregation management information indicates settings related to hash calculation performed by the hash calculation unit 123. Specifically, the aggregation management information includes frame part specifying information for specifying frame part information, calculation contents information indicating calculation contents of hash calculation, in order for the switching determination unit 122 to determine a physical link that outputs a frame, It has effective physical link number information indicating the number of usable physical links in each of the active output unit 181 and the standby output unit 182, and operation non-execution information indicating that hash calculation is not performed. Further, the aggregate management information includes frame discard information indicating whether to discard the frame.

  The aggregate destination management information storage unit 153 stores aggregate destination management information indicating a physical link to which a frame is output. Here, the aggregated destination management information is stored in the aggregated destination management information storage unit 153 by configuring aggregated destination management tables 153a and 153b described later in detail with reference to FIGS. The aggregate destination management information includes working physical link information that identifies the physical link of the working output unit 181 and standby physical link information that identifies the physical link of the standby output unit 182. Here, the physical link is each port (for example, port # 0,..., Port # 7, etc.) that the active output unit 181 and the standby output unit 182 have. Further, the aggregate destination management information is associated with each hash value calculated by the hash calculation unit 123 and each physical link indicated by the working physical link information, and each hash calculated by the hash calculation unit 123 The value is associated with each physical link indicated by the standby physical link information.

  The aggregated destination management information storage unit 153 is configured by a dual port memory. Further, in the physical link specifying information, a part of the address stored in the aggregated destination management information storage unit 153 is associated with the active system output unit 181 and the standby system output unit 182, and the other part of the address is a physical address. Associated with a link.

  The active output unit 181 is configured by a part of physical links among the physical links that constitute the logical link. The standby output unit 182 includes a part or all of the physical links of the physical links other than the physical links forming the active output unit 181 among the physical links forming the logical link. The number of physical links configuring the active system output unit 181 and the number of physical links configuring the standby system output unit 182 are the same (for example, 8). Here, the working system output unit 181 and the standby system output unit 182 have 8 communication ports, and a total of 16 communication ports constitute one logical link.

  The terminal device 40 is communicably connected to the switch 100 and can display information obtained by communicating with the switch 100. The switch 100 includes a communication unit 140 that can communicate with the terminal device 40. The terminal device 40 can acquire the aggregated destination management information and the aggregated destination statistical information by communication with the switch 100 via the communication unit 140. The terminal device 40 includes a display unit (not shown) that can display the acquired aggregate destination management information and the aggregate destination statistical information.

  The switch 100 includes a plurality of (for example, four) interface cards 102a, 102b, 102c, and 102d shown in FIG. Here, an interface card to which a frame is input is an input card (for example, interface card 102a), and an interface card to which a frame is output is an output card (for example, interface cards 102b and 102c). It is functionally the same, and frames can be input and output on each card. That is, the switch 100 is input by an input card that functions as the input unit 110, the distribution unit 120, and the failure detection unit 130, and two output cards that respectively function as the active output unit 181 and the standby output unit 182. Output the frame to another switch.

  The switch 100 can also communicate using a plurality of logical links by using an output card (for example, the active system output unit 181 and the standby system output unit 182) having a plurality of physical links. For each logical link, the allocating unit 120 can arbitrarily set whether the logical link is configured by a physical link of one output card or a physical link that configures a plurality of output cards. Based on this setting, the logical link of the switch 100 can be composed of physical links that constitute one output card, and can be composed of physical links that constitute a plurality of output cards.

  In the present embodiment, for example, a logical link configured by aggregating physical links is configured by using a plurality of interface cards each having a plurality of communication ports, such as the interface cards 102a, 102b, 102c, and 102d. . At this time, each communication port communicates as a physical link. That is, this logical link is composed of a plurality of interfaces having a plurality of ports.

  In the present embodiment, for example, a 2 × N port logical link is configured by using two cards having N (for example, 8) ports. By using the N ports of the one interface card as a working interface card for communication, and setting the N ports of the other interface card as a standby interface card in a standby state, redundancy is achieved between the interfaces. Give sex. This is called an N: N link configuration from the number of ports (physical links) of each interface card.

  At this time, in this logical link, the number of ports that the user can use for communication is N ports. In the event of a failure of the working interface card, the port of the working interface card is changed to an unused state, and the N ports of the standby interface card are changed from the unused state to the usable state, thereby using the interface to be used. Switch cards. Thereby, it is possible to continue to provide logical links with N ports even when a failure occurs. In addition, even when the working interface card in which a failure has occurred is replaced, the influence on the communication due to the replacement is prevented.

  FIG. 6 is a diagram illustrating a data structure example of the flow destination management table according to the first embodiment. The flow destination management table 151 a illustrated in FIG. 6 is stored in the table storage memory 104. The table storage memory 104 functions as the flow destination management information storage unit 151. The flow destination management table 151a is a table indicating whether or not a link that is a transmission destination of each frame constitutes a logical link. The flow destination management table 151a is provided with an “L” field indicating whether or not a destination port to which the frame is transmitted constitutes a logical link, and a “destination” field indicating a destination to which the frame is output. . Information arranged in the horizontal direction of each field is associated with each other.

  Information indicating whether the destination port of the frame constitutes a logical link is set in the L field. Specifically, when the destination port of the frame is not a logical link, “0” is set. On the other hand, when the destination port of the frame is a logical link, “1” is set.

  In the destination field, when the destination of the frame is a logical link, a LAG number described later in FIG. 7 is set. On the other hand, when the destination port of the frame is not a logical link, information indicating the destination card name indicating the interface card that transmits the frame and the port number is set.

The flow destination management table 151 a is stored in the table storage memory 104 in response to an operation input by the administrator of the switch 100.
FIG. 7 illustrates an exemplary data structure of the aggregation management table according to the first embodiment. The aggregation management table 152 a illustrated in FIG. 7 is stored in the table storage memory 104. The table storage memory 104 functions as the aggregate management information storage unit 152. The aggregation management table 152a is a table for determining a logical link to which each frame is transmitted. The aggregation management table 152a includes a “V” field indicating whether each link is valid, a “LAG number” field indicating a LAG number for allocating a link aggregation destination, and a logical link for transmitting a frame. "SEL" field indicating whether the current system is the active system or the standby system, "NH" field indicating whether or not to perform hash calculation (to be described later) in frame allocation, and the object of hash calculation when performing hash calculation "HT" field indicating the value to be performed, "HR" field indicating the rule of hash calculation, the number of ports that can be used in the logical link of the active system, or the logical link of the active system when hash calculation is not performed based on the NH field The “working AP” field indicating the transmission port in the network, and the number of ports that can be used in the standby logical link. It is "pre-AP" field indicates a delivery port in the logical link in the backup of the case without a hash computed based on NH field is provided. Information arranged in the horizontal direction of each field is associated with each other.

  In the V (Valid) field, information indicating whether each link by the switch 100 is valid is set. If the link is valid, “0” is set. On the other hand, if the link is invalid, such as when a failure occurs in the switch, each interface, or link aggregation, “1” is set.

  In the LAG number field, a LAG number for assigning link aggregation destinations is set. According to the LAG number, it is determined which of the link aggregation distribution patterns preset in the aggregation management table 152a is to be allocated.

  In the SEL (Selector) field, information indicating whether a logical link for transmitting a frame is an active system or a standby system is set. Specifically, “0” is set when a frame is transmitted through the working logical link. On the other hand, when a failure occurs in the active logical link, the active logical link is switched to the standby logical link, and a frame is transmitted on the standby logical link, the above "0" to "1" Rewritten to be set.

  In the NH (No Hash) field, information indicating whether or not hash calculation is performed in frame allocation is set. Specifically, “0” is set when hash calculation is performed in the distribution of frames. On the other hand, when hash calculation is not performed in the distribution of frames, “1” is set.

  In the HT (Hash Target) field, a value to be subjected to hash calculation when hash calculation is performed is set. Specifically, “0” is set when the value to be subjected to hash calculation is the MAC address of the frame. Also, “1” is set when the value for hash calculation is the VLAN ID of the frame. Also, “2” is set when the value targeted for hash calculation is an IP address.

  Information indicating a rule for hash calculation is set in an HR (Hash Rule) field. Specifically, “0” is set when hash calculation is performed using a remainder obtained by dividing a target value by the number of Active Ports described later as a hash value. When hash calculation is performed using a remainder obtained by dividing a target value by a generator polynomial as a hash value, “1” is set.

  In the active AP (Active Port) field, information indicating the number of ports that can be used in the working logical link or the transmission port in the working logical link when hash calculation is not performed based on the NH field is set. . Specifically, in principle, the number of ports that can be used in the working logical link at that time is set. When the setting value of the NH field is 1, the value of the HV field of the aggregate destination management table 153a (or the address of the aggregate destination management table 153b) indicating the port to which the frame is transmitted in the working logical link is directly set. The

  In the backup AP field, information indicating the number of ports that can be used in the backup logical link or the transmission port in the backup logical link when hash calculation is not performed based on the NH field is set. Specifically, in principle, the number of ports that can be used in the backup logical link at that time is set. When the setting value of the NH field is 1, the value of the HV field of the aggregate destination management table 153a (or the address of the aggregate destination management table 153b) indicating the port to which the frame is transmitted in the backup logical link is directly set. The

  Specifically, in the example shown in the third line from the top of the aggregation management table 152a, the setting value of the NH field is “0”, and the hash calculation unit 123 performs the hash calculation. Then, it is output by a logical link according to the result of this hash calculation. The value “8” of the working AP at this time indicates the number of ports that can be used in the current working logical link. When a failure occurs in the physical link and the number of usable ports decreases, the failure detection unit 130 rewrites the value so as to decrease this value. On the other hand, in the example shown in the fourth line from the top of the aggregation management table 152a, the setting value of the NH field is “1”. In this case, the hash calculation by the hash calculation unit 123 is not performed, but is output from the physical ports constituting the logical link. The value “3” of the working AP at this time indicates the port of the physical link in the current working logical link. Although the working AP has been described, the same applies to the backup AP.

  The aggregation management table 152 a is stored in the table storage memory 104 in response to an operation input by the administrator of the switch 100. In the aggregation management table 152a, the setting value changes according to the change in the number of usable ports in the active and standby logical links.

  When a failure occurs in the communication port of the active output unit 181 and the logical link is switched to the standby output unit 182, the SEL field of the aggregation management table 152a is rewritten from “0” to “1”. In addition, the number of ports that can be used at that time of the standby output unit 182 that will be the next active system from the number of ports that can be used at that time (the number of active ports, for example, 7) in the active AP field. Rewrite as

  In this way, the active AP and the standby AP are provided in the aggregation management table 152a, and the active system output unit can be set for each of the active system output unit 181 and the standby system output unit 182. It is possible to save the trouble of rewriting the AP field when switching from 181 to the standby output unit 182.

  FIG. 8 is a diagram illustrating a data structure example of the aggregated destination management table according to the first embodiment. The aggregated destination management table 153a shown in FIG. 8 is stored in the table storage memory 104. The table storage memory 104 functions as the aggregate destination management information storage unit 153. The aggregated destination management table 153a is a table indicating a destination port that is a communication port to which each frame in the logical link is transmitted. In the aggregated destination management table 153a, the “HV” field indicating the correspondence between the hash value assigned to the frame and the destination port to which the frame is transmitted, and the “working DP” field indicating the destination port in the working logical link , And a “spare DP” field indicating the destination port in the backup logical link. Information arranged in the horizontal direction of each field is associated with each other.

In the HV field (Hash Value), a value indicating the correspondence between the hash value assigned to the frame and the communication port to which the frame is transmitted is set.
In the working DP (Destination Port) field, information for uniquely identifying a destination port which is a communication port to which a frame is transmitted in the working logical link is set.

Information for uniquely identifying a destination port which is a communication port to which a frame is transmitted in the backup logical link is set in the backup DP field.
The aggregate destination management table 153 a is stored in the table storage memory 104 in response to an operation input by the administrator of the switch 100.

  As described above, according to the first embodiment, it is possible to switch from the active system to the standby system at high speed only by rewriting only the SEL field of the aggregation management table 152a when a failure occurs.

  In addition, by setting an arbitrary value in the HT field in units of logical links, a specific frame field can be targeted for hash calculation. Thereby, it is possible to increase the degree of freedom of frame allocation by making it possible to select the field of the frame to be calculated for link aggregation hash calculation.

In addition, the NH field can be selected to aggregate the distribution destinations into one without performing the link aggregation hash calculation.
In addition, it is possible to select a calculation method for hash calculation by setting an arbitrary value in the HR field in the link aggregation unit.

  In addition, the number of ports that can be used at that time can be set for each of the active system and the standby system. As a result, even if a failure occurs in the port, if the number of ports corresponding to the bandwidth required for the link is satisfied, the logical link is not switched and a failure occurs in the port. The logical link can be switched after the required bandwidth is not satisfied.

  Further, when the frame discarding unit 125 discards the frame, when all the output units and all the ports constituting the logical link have failed, or when the switch 100 has failed, it is unnecessary. It is possible to prevent frames from being transmitted from the switch 100, and it is possible to reduce the load of frame transmission / reception processing within the switch.

  Further, when the communication unit 140 outputs data indicating the operation status of the switch 100 to the terminal device 40, the network maintenance person and the shim system maintenance person can always monitor and control the operation state of the logical link. It becomes possible to improve the reliability of network communication using the.

<Modification of the first embodiment>
Next, a modification of the first embodiment will be described. Differences from the first embodiment will be mainly described, and the same reference numerals are used for the same matters, and descriptions thereof are omitted. The switch of this modification is different in that the working DP and the backup DP are stored in different addresses in the aggregate destination management table 153b.

  When the working DP and the spare DP are stored in the same address of the aggregate destination management table, it is possible to efficiently use the memory capacity of the table, but when the working system is the active system, the frame input When the aggregated destination management table is always accessed based on the settings, when the setting frame is input and DP setting or change of the non-active system is performed, access from the input packet and the standby system setting are performed. There is a possibility that an access collision (contention) that occurs at the same time as the access of the frame for use occurs. In this case, it is necessary to add an access arbitration control circuit for avoiding this access collision, resulting in a complicated circuit and an increase in the cost of the apparatus.

  FIG. 9 is a diagram illustrating an example of the data structure of the aggregated destination management table in the modification of the first embodiment. In this modification, as shown in FIG. 9, the aggregated destination management table 153b is assigned to different addresses for the working DP and the backup DP, and a separate area is given to each. As the address of each area, a value obtained by bit-combining the value of the SEL field of the aggregation management table 152a in FIG. 7 and the value of the hash calculation result in the figure is assigned.

  Also, the aggregated destination management table 153b in the figure is stored in the dual port memory. For example, in the spare DP, the port # 7 of the standby output unit 182 is bit-coupled with the value “1” of the SEL field and the DP address “7” in the aggregate destination management table 153b, and is “0x17” in hexadecimal notation. It has become. In the aggregate destination management table 153b, this address associates the relationship between the hash value assigned to the frame and the communication port to which the frame is transmitted. Here, the dual port memory is a memory provided with two ports for data input / output. While reading data from one port, it is possible to write data from the other port. Thereby, data can be read and written at high speed. Thus, by assigning the working DP and the spare DP to different addresses, it is possible to provide setting changes and registration on the non-operating system side without causing access collision even in the operating state.

  The aggregated destination management table 153 b shown in FIG. 9 is stored in the table storage memory 104. Similar to the aggregated destination management table 153a, the aggregated destination management table 153b is a table indicating a destination port that is a communication port to which each frame in the logical link is transmitted. The aggregated destination management table 153b stores information for uniquely identifying the destination port in the working or protection logical link associated with the hash value of the frame at the above address. The aggregate destination management table 153 b is stored in the table storage memory 104 in response to an operation input by the administrator of the switch 100.

  As described above, according to the present modification, in the aggregated destination management table 153b, by assigning the active DP and the spare DP to areas having different addresses, the setting change or registration on the non-operating system side is performed. Can be performed without causing access collision.

[Second Embodiment]
Next, a second embodiment will be described. Differences from the first embodiment will be mainly described, and the same reference numerals are used for the same matters, and descriptions thereof are omitted.

  The second embodiment is that the statistical information writing unit 226 of the distribution unit 220 writes and stores the total result of the number of frames output from each physical link in the aggregate destination statistical information storage unit 254. This is different from the first embodiment.

Below, the distribution part 220 in this Embodiment is demonstrated. FIG. 10 is a block diagram illustrating functions of the distribution unit according to the second embodiment.
In addition to the flow destination determination unit 121, the switching determination unit 122, the hash calculation unit 123, the distribution destination determination unit 124, and the frame discard unit 125, the distribution unit 220 according to this embodiment includes a frame output from each physical link. The statistical information writing unit 226 is included. Further, the switch (not shown) of the present embodiment is similar to the switch 100 of the first embodiment, and includes an input unit (not shown), a distribution unit 220, a failure detection unit 130, a communication unit 140, and a flow destination management information storage unit 151. In addition to the aggregate management information storage unit 152, the aggregate destination management information storage unit 153, the active system output unit 181, the standby system output unit 182, in order to store the aggregate result of the number of frames output from each physical link, A destination statistical information storage unit 254 is included.

Similarly to the input unit 110 of the first embodiment, the input unit receives a frame transferred to a communication device such as another switch or a terminal device by the switch of the present embodiment.
The distribution unit 220 refers to the aggregated destination management information stored as the aggregated destination management table in the aggregated destination management information storage unit 153 by the input unit 110 as in the case of the allocated unit 120 of the first embodiment. The physical link from which the input frame is output is determined as one of the physical links that constitute the logical link.

  As in the first embodiment, the flow destination determination unit 121 refers to the flow destination management information stored in the flow destination management information storage unit 151 and configures the physical link from which the frame is output as a logical link. Or one of the physical links (not shown) other than the physical links constituting the logical link.

  Similar to the first embodiment, the switching determination unit 122 rewrites the aggregate management information from the active state to the standby state when detecting a switching instruction from the failure detection unit 130. Based on this, the distribution destination determination unit 124 that refers to the aggregation management information determines the physical link from which the frame is output from the active output unit 181 and the standby output unit 182. Further, the switching determination unit 122 refers to the aggregation management information and causes the hash calculation unit 123 to perform hash calculation. At this time, the switching determination unit 122 extracts frame part information from the entire frame based on the frame part specifying information, and causes the hash calculation unit 123 to perform hash calculation using the extracted frame part information. Further, the switching determination unit 122 causes the hash calculation unit 123 to perform hash calculation based on the calculation content information. Further, when detecting the operation non-execution information, the switching determination unit 122 determines a physical link that outputs a frame without causing the hash calculation unit 123 to perform hash calculation.

  As in the first embodiment, the hash calculation unit 123 adds the same number of types as the number of physical links of the active output unit 181 and the standby output unit 182 to the frame part information that constitutes a part of the frame. A hash value is calculated using a hash function that can take a value.

  As in the first embodiment, the distribution destination determination unit 124 determines a physical port from which a frame is output based on the determination by the flow destination determination unit 121. The distribution destination determination unit 124 refers to the aggregate management information to switch from the active state to the standby state, and refers to the aggregate destination management information, based on the hash value obtained by the hash calculation unit 123 calculating. The physical link to which the frame is output is determined.

  As in the first embodiment, the frame discard unit 125 discards a frame when the frame discard information included in the aggregated destination management information indicates that the frame is to be discarded. Thereby, when performing a test about the operation of the switch 100 and the connection destination, it is possible to limit the frames to be output when the frame is transmitted only to a specific transmission destination or only to a specific transmission destination.

  The statistical information writing unit 226 functions in the same manner as the distribution destination determination unit 124 and is obtained by the hash calculation unit 123 calculating with reference to the aggregation management information stored in the aggregation management information storage unit 152. Based on the determined hash value, the physical link from which the frame is output is determined, and the aggregated destination statistical information on the total number of frames output from each physical link of the determined active output unit 181 and the standby output unit 182 Is written into the aggregated destination statistical information storage unit 254. As a result, the statistical information writing unit 226 determines the physical link for outputting the frame in the same manner as the distribution destination determination unit 124 in parallel with the distribution destination determination unit 124, and the frame input based on the determination is determined. Aggregate the output physical links.

  As in the first embodiment, the failure detection unit 130 detects the occurrence of a failure in the physical link constituting the active output unit 181 and outputs a switching instruction when the occurrence of the failure is detected.

  As in the first embodiment, the flow destination management information storage unit 151 uses a physical link that outputs a frame as a physical link that constitutes a logical link, or a physical link other than a physical link that constitutes a logical link. The flow destination management information indicating whether or not to be stored is stored.

  As in the first embodiment, the aggregate management information storage unit 152 outputs the frame from the physical link configuring the active output unit 181 or the physical link configuring the standby output unit 182. Is stored.

  Further, the aggregation management information indicates the setting related to the hash calculation performed by the hash calculation unit 123, as in the first embodiment. Specifically, the aggregation management information includes frame part specifying information for specifying frame part information, calculation contents information indicating calculation contents of hash calculation, in order for the switching determination unit 122 to determine a physical link that outputs a frame, It has effective physical link number information indicating the number of usable physical links in each of the active output unit 181 and the standby output unit 182, and operation non-execution information indicating that hash calculation is not performed. Further, the aggregate management information includes frame discard information indicating whether to discard the frame.

  The aggregate destination management information storage unit 153 stores aggregate destination management information indicating a physical link to which a frame is output, as in the first embodiment. Here, the aggregated destination management information constitutes the aggregated destination management tables 153a and 153b and is stored in the aggregated destination management information storage unit 153. The aggregate destination management information includes working physical link information that identifies the physical link of the working output unit 181 and standby physical link information that identifies the physical link of the standby output unit 182. The physical link is each port that the active output unit 181 and the standby output unit 182 have. Further, the aggregate destination management information is associated with each hash value calculated by the hash calculation unit 123 and each physical link indicated by the working physical link information, and each hash calculated by the hash calculation unit 123 The value is associated with each physical link indicated by the standby physical link information.

  The aggregated destination management information storage unit 153 is configured by a dual port memory as in the first embodiment. Further, in the physical link specifying information, a part of the address stored in the aggregated destination management information storage unit 153 is associated with the active system output unit 181 and the standby system output unit 182, and the other part of the address is a physical address. Associated with a link.

  The aggregated destination statistical information storage unit 254 stores aggregated destination statistical information that is a totaled result of the number of frames output from each physical link of the active output unit 181 and the standby output unit 182. The aggregated destination statistical information storage unit 254 is configured by a dual port memory, like the aggregated destination management information storage unit 153. In addition, the aggregate destination statistical information includes a part of the address stored in the aggregate destination statistical information storage unit 254 being associated with the active system output unit 181 and the standby system output unit 182, and another part of the address is physical. Associated with a link.

  As in the first embodiment, the active output unit 181 includes a part of physical links that constitute a logical link. The standby output unit 182 includes a part or all of the physical links of the physical links other than the physical links forming the active output unit 181 among the physical links forming the logical link. The number of physical links configuring the active system output unit 181 and the number of physical links configuring the standby system output unit 182 are the same (for example, 8).

  The communication unit 140 sends the aggregate destination management information stored in the aggregate destination management information storage unit 153 and the aggregate destination statistical information stored in the aggregate destination statistical information storage unit 254 to the terminal device (not shown). Output. Similarly to the terminal device of the first embodiment, the terminal device is communicably connected to the communication unit 140 included in the switch of the present embodiment, and can display information obtained by communicating with the communication unit 140. it can. The terminal device can acquire the aggregate destination management information and the aggregate destination statistical information by communication via the communication unit 140. The terminal device includes a display unit (not shown) that can display the acquired aggregate destination management information and aggregate destination statistical information.

  FIG. 11 is a diagram illustrating an example of a data structure of an aggregate destination statistics table according to the second embodiment. In this embodiment, as shown in FIG. 11, the aggregated destination statistics table 254a is assigned to different addresses in the working DP and the backup DP, and a separate area is given to each.

  Also, the aggregated destination statistics table 254a in the figure is stored in the dual port memory, like the aggregated destination management table 153b in FIG. For example, in the standby DP, the port # 7 of the standby output unit 182 (16th line from the top in the aggregate destination statistics table 254a) has the value “1” in the SEL field and the DP address “7” in the aggregate destination management table 153b. "Is bit-combined to be" 0x17 "in hexadecimal notation. In the aggregate destination statistics table 254a, this address associates the relationship between the communication port to which the frame is transmitted and the number of frames transmitted from the communication port.

  The aggregated destination statistics table 254a illustrated in FIG. 11 is stored in the table storage memory 104. The table storage memory 104 functions as the aggregate destination statistical information storage unit 254. The aggregated destination statistics table 254a is a table that indicates the aggregated result of the number of frames transmitted from the communication port. The aggregated destination statistics table 254a stores information indicating the number of frames transmitted from the destination port in the working or protection logical link, which is associated with the frame hash value at the above address. The aggregate destination statistics table 254a is stored in the table storage memory 104 in accordance with the writing of the aggregation results by the statistics information writing unit 226.

  As described above, according to the second embodiment, the statistical information writing unit 226 is switched from the switch based on the processing of the switching determination unit 122 and the hash calculation unit 123 and the aggregated destination management table 153a (or 153b). When the frame distribution function of the switch 100 is tested by counting the output frames and storing information indicating the number of frames transmitted from each communication port in the aggregate destination statistics table 254a, The result can be easily obtained.

  At this time, the statistical information writing unit 226 calculates the physical link from which the frame is output and the allocation destination determination unit 124 that determines the physical link from which the frame is output. The effect on it can be kept to a minimum.

[Third Embodiment]
Next, a third embodiment will be described. Here, the description will focus on differences from the second embodiment described above, and the same reference numerals are used for the same matters, and descriptions thereof are omitted.

  In the third embodiment, the statistical information writing unit 326 of the allocating unit 320 displays the aggregated result of the number of frames output from each physical link stored in the aggregated destination management information storage unit 153 as the aggregated destination. It differs from the second embodiment in that it is written and stored in the statistical information storage unit 254.

Below, the distribution part 320 in this Embodiment is demonstrated. FIG. 12 is a block diagram illustrating functions of the distribution unit according to the third embodiment.
In addition to the flow destination determination unit 121, the switching determination unit 122, the hash calculation unit 123, the distribution destination determination unit 124, and the frame discard unit 125, the distribution unit 320 according to this embodiment includes a frame output from each physical link. Statistical information writing unit 326 is included. Further, the switch (not shown) of the present embodiment is similar to the second embodiment in that the input unit (not shown), the distribution unit 320, the failure detection unit 130, the communication unit 140, the flow destination management information storage unit 151, the aggregation management In addition to the information storage unit 152, the aggregated destination management information storage unit 153, the active system output unit 181, and the standby system output unit 182, aggregated destination statistical information is stored in order to store the total result of the number of frames output from each physical link. A storage unit 254 is included.

As in the second embodiment, the input unit receives a frame transferred to a communication device such as another switch and a terminal device by the switch of this embodiment.
The distribution unit 320 refers to the aggregated destination management information stored as the aggregated destination management table in the aggregated destination management information storage unit 153 by the input unit 110 in the same manner as the distribution unit 220 of the second embodiment. The physical link from which the input frame is output is determined as one of the physical links that constitute the logical link.

  As in the second embodiment, the flow destination determination unit 121 refers to the flow destination management information stored in the flow destination management information storage unit 151 and configures the physical link from which the frame is output as a logical link. Or one of the physical links (not shown) other than the physical links constituting the logical link.

  Similar to the second embodiment, the switching determination unit 122 rewrites the aggregate management information from indicating the current status to indicating the standby status when the switching instruction from the failure detection unit 130 is detected. Based on this, the distribution destination determination unit 124 that refers to the aggregation management information determines the physical link from which the frame is output from the active output unit 181 and the standby output unit 182. Further, the switching determination unit 122 refers to the aggregation management information and causes the hash calculation unit 123 to perform hash calculation. At this time, the switching determination unit 122 extracts frame part information from the entire frame based on the frame part specifying information, and causes the hash calculation unit 123 to perform hash calculation using the extracted frame part information. Further, the switching determination unit 122 causes the hash calculation unit 123 to perform hash calculation based on the calculation content information. Further, when detecting the operation non-execution information, the switching determination unit 122 determines a physical link that outputs a frame without causing the hash calculation unit 123 to perform hash calculation.

  As in the second embodiment, the hash calculation unit 123 adds the same number of types as the number of physical links included in the active output unit 181 and the standby output unit 182 to the frame part information constituting a part of the frame. A hash value is calculated using a hash function that can take a value.

  As in the second embodiment, the distribution destination determination unit 124 determines a physical port from which a frame is output based on the determination by the flow destination determination unit 121. The distribution destination determination unit 124 refers to the aggregate management information to switch from the active state to the standby state, and refers to the aggregate destination management information, based on the hash value obtained by the hash calculation unit 123 calculating. The physical link to which the frame is output is determined.

  As in the second embodiment, the frame discard unit 125 discards the frame when the frame discard information included in the aggregate destination management information indicates that the frame is to be discarded. Thereby, when performing a test about the operation of the switch 100 and the connection destination, it is possible to limit the frames to be output when the frame is transmitted only to a specific transmission destination or only to a specific transmission destination.

  The statistical information writing unit 326 monitors the physical links of the active system output unit 181 and the standby system output unit 182, totals the number of frames actually output from each physical link, and aggregates the aggregated result statistical information Is written into the aggregated destination statistical information storage unit 254.

  As in the second embodiment, the failure detection unit 130 detects the occurrence of a failure in the physical link constituting the active output unit 181 and outputs a switching instruction when the occurrence of the failure is detected.

  As in the second embodiment, the flow destination management information storage unit 151 uses a physical link that outputs a frame as a physical link that constitutes a logical link, or a physical link other than a physical link that constitutes a logical link. The flow destination management information indicating whether or not to be stored is stored.

  As in the second embodiment, the aggregate management information storage unit 152 outputs the frame from the physical link configuring the active output unit 181 or the physical link configuring the standby output unit 182. Is stored.

  Further, the aggregation management information indicates the setting related to the hash calculation performed by the hash calculation unit 123, as in the second embodiment. Specifically, the aggregation management information includes frame part specifying information for specifying frame part information, calculation contents information indicating calculation contents of hash calculation, in order for the switching determination unit 122 to determine a physical link that outputs a frame, It has effective physical link number information indicating the number of usable physical links in each of the active output unit 181 and the standby output unit 182, and operation non-execution information indicating that hash calculation is not performed. Further, the aggregate management information includes frame discard information indicating whether to discard the frame.

  The aggregated destination management information storage unit 153 stores aggregated destination management information indicating a physical link to which a frame is output, as in the second embodiment. Here, the aggregated destination management information constitutes the aggregated destination management tables 153a and 153b and is stored in the aggregated destination management information storage unit 153. The aggregate destination management information includes working physical link information that identifies the physical link of the working output unit 181 and standby physical link information that identifies the physical link of the standby output unit 182. The physical link is each port that the active output unit 181 and the standby output unit 182 have. Further, the aggregate destination management information is associated with each hash value calculated by the hash calculation unit 123 and each physical link indicated by the working physical link information, and each hash calculated by the hash calculation unit 123 The value is associated with each physical link indicated by the standby physical link information.

  The aggregated destination management information storage unit 153 is configured by a dual port memory as in the second embodiment. Further, in the physical link specifying information, a part of the address stored in the aggregated destination management information storage unit 153 is associated with the active system output unit 181 and the standby system output unit 182, and the other part of the address is a physical address. Associated with a link.

  The aggregated destination statistical information storage unit 254 stores aggregated destination statistical information that is the aggregated result of the number of frames output from each physical link of the active system output unit 181 and the standby system output unit 182, as in the second embodiment. Remember. The aggregated destination statistical information storage unit 254 is configured by a dual port memory, like the aggregated destination management information storage unit 153. In addition, the aggregate destination statistical information includes a part of the address stored in the aggregate destination statistical information storage unit 254 being associated with the active system output unit 181 and the standby system output unit 182, and another part of the address is physical. Associated with a link.

  As in the second embodiment, the active output unit 181 includes a part of physical links that constitute a logical link. The standby output unit 182 includes a part or all of the physical links of the physical links other than the physical links forming the active output unit 181 among the physical links forming the logical link. The number of physical links configuring the active system output unit 181 and the number of physical links configuring the standby system output unit 182 are the same (for example, 8).

  As in the second embodiment, the communication unit 140 receives the aggregate destination management information stored in the aggregate destination management information storage unit 153 and the aggregate destination statistical information stored in the aggregate destination statistical information storage unit 254. Output to a terminal device (not shown). Similarly to the terminal device of the first embodiment, the terminal device is communicably connected to the communication unit 140 included in the switch of the present embodiment, and can display information obtained by communicating with the communication unit 140. it can. The terminal device can acquire the aggregate destination management information and the aggregate destination statistical information by communication via the communication unit 140. The terminal device includes a display unit (not shown) that can display the acquired aggregate destination management information and aggregate destination statistical information.

  As described above, according to the third embodiment, the statistical information writing unit 326 monitors each physical link of the active system output unit 181 and the standby system output unit 182 to output from the switch. Aggregate frames. Then, the statistical information writing unit 326 stores information indicating the number of frames transmitted from each communication port in the aggregate destination statistical table 254a, thereby performing the test on the frame distribution function of the switch 100. Minute results can be easily obtained.

  At this time, the statistical information writing unit 326 monitors and counts the actually output frames, so that the number of frames actually output can be totaled and the configuration necessary for the totalization is simplified. be able to.

[Fourth Embodiment]
Next, a fourth embodiment will be described. Differences from the first embodiment will be mainly described, and the same reference numerals are used for the same matters, and descriptions thereof are omitted.

  The fourth embodiment has a plurality of output units, a part of the plurality of output units is set as an active output unit, and the other output units are set as standby output units. To do. Then, the frame is output from the physical link constituting the active output unit. On the other hand, the standby output unit is normally on standby, and if there is a failure in the active output unit, replace a part of the standby output unit with the active output unit. This is different from the first embodiment in that it switches to the output unit of the operational system.

Hereinafter, the switch 400 in the present embodiment will be described. FIG. 13 is a block diagram illustrating functions of a switch according to the fourth embodiment.
The switch 400 in this embodiment includes a plurality of output units 481a, 481b,. Further, the switch 400 of the present embodiment is configured so that a link of a communication network having a redundant configuration by link aggregation is changed from a physical link that configures an active output unit to a standby output unit based on a switching instruction. Are input unit 110, distribution unit 420, failure detection unit 130, communication unit 140, flow destination management information storage unit 151, aggregate management information storage unit 452, and aggregate destination management information storage unit 453. The distribution unit 420 includes a flow destination determination unit 121, a switching determination unit 422, a hash calculation unit 123, a distribution destination determination unit 424, and a frame discard unit 125.

  Here, the active output unit is an output unit used to output the current frame. The standby output unit is not used for outputting the current frame, and is an output unit that waits in a state in which a frame can be output in preparation for a failure of the active output unit. The active output unit is an output unit set as the active output unit in the initial state and the normal state. The standby output unit is an output unit set as the standby output unit in the initial state and the normal state.

As in the first embodiment, the input unit 110 receives a frame transferred to a communication device such as another switch or a terminal device by the switch 400 according to the present embodiment.
The allocating unit 420 refers to the aggregated destination management information stored in the aggregated destination management information storage unit 453 as the aggregated destination management table, and outputs physical links that output frames as output units 481a, 481b,. A physical link that configures one output unit of 481z is set, and a physical link that outputs a frame is switched to a physical link that configures another output unit in response to a switching instruction.

  In the switching instruction, when a failure occurs in communication between the switch 400 and another switch through a logical link, the failure detection unit 130 detects the occurrence of the failure. Then, the failure detection unit 130 outputs a switching instruction to the switching determination unit 422 of the distribution unit 420 based on the detection of the occurrence of the failure. Based on the switching by the allocating unit 420, the active output unit changes from the output unit 481a, which is the active output unit that is currently outputting the frame, to one of the standby output units (for example, the output unit 481b). Can be switched to. After this switching, the frame is output from the output unit 481b of the standby system accordingly.

  In addition, the distribution unit 420 switches the active output unit based on the number of usable physical links. When the number of physical links indicated by the effective physical link information of the output unit 481a that is the output unit of the active system is less than the band indicated by the band information, the allocating unit 420 determines the output unit of another standby system. Switch one of them to the active output. Band information indicating a band to be secured for transmitting the frame is set in the frame transmitted by the switch 400 according to the transmission destination. This band information is stored in a storage unit (not shown) included in the switch 400.

  As in the first embodiment, the flow destination determination unit 121 refers to the flow destination management information stored in the flow destination management information storage unit 151 and configures the physical link from which the frame is output as a logical link. Or one of the physical links (not shown) other than the physical links constituting the logical link.

  When the switching determination unit 422 detects a switching instruction from the failure detection unit 130, the switching determination unit 422 sets the output unit 481a set as the output unit of the active system as the output unit of the standby system, and outputs the standby system output unit 481b, In response to the switching instruction to switch the active output unit by setting at least one of the output units 481b,..., 481z set to 481z as the active output unit, The aggregation management information stored in the aggregation management information storage unit 452 is replaced with the output unit 481a that is the output unit of the active system, and is an output unit 481b that is the output unit of the standby system and that is the target of the switching instruction. .., 481z is newly set as the output unit of the operational system. Specifically, at this time, the switching determination unit 422 rewrites the aggregation management information to reflect the setting. Based on this, the distribution destination determination unit 424 that refers to the aggregation management information determines a physical link to which a frame is output from among the output units 481b,. Accordingly, it is possible to realize card redundancy in which one output unit is allocated to the active system and a plurality (N) of output units are allocated to the standby system (N: 1).

  The switching determination unit 422 causes the hash calculation unit 123 to perform hash calculation with reference to the aggregation management information, similarly to the switching determination unit 122 according to the first embodiment. At this time, the switching determination unit 422 extracts frame part information from the entire frame based on the frame part specifying information, and causes the hash calculation unit 123 to perform hash calculation using the extracted frame part information. Also, the switching determination unit 422 causes the hash calculation unit 123 to perform hash calculation based on the calculation content information. Furthermore, when the operation non-execution information is detected, the switching determination unit 422 determines a physical link that outputs a frame without causing the hash calculation unit 123 to perform hash calculation.

  The hash calculation unit 123 uses a hash function that can take the same number of types of values as the number of physical links included in each output unit 481a, 481b,. To calculate the hash value.

  The distribution destination determination unit 424 sets a physical link that outputs a frame in advance as a physical link that constitutes the output unit 481a that is set as the output unit of the active system. When a failure occurs in the physical link of the active output unit, the distribution destination determination unit 424 refers to the aggregation management information stored in the aggregation management information storage unit 452 and outputs a frame. The physical link is switched to the physical link constituting the output unit 481b,..., 481z of the standby system.

  Here, the distribution destination determination unit 424 refers to the aggregation management information and switches the active output unit 481a to any one of the standby output units 481a, 481b,. With reference to the information, the physical link to which the frame is output is determined based on the hash value obtained by the calculation by the hash calculation unit 123.

  As in the first embodiment, the frame discard unit 125 discards a frame when the frame discard information included in the aggregated destination management information indicates that the frame is to be discarded. Thus, when testing the operation of the switch 400 and the connection destination, the frames to be output can be limited when the frame is transmitted only to a specific transmission destination or only to other than the specific transmission destination.

The failure detection unit 130 detects the occurrence of a failure in the physical link configuring the active output unit 481a, and outputs a switching instruction when the occurrence of the failure is detected.
As in the first embodiment, the flow destination management information storage unit 151 uses a physical link that outputs a frame as a physical link that constitutes a logical link, or a physical link other than a physical link that constitutes a logical link. The flow destination management information indicating whether or not to be stored is stored.

The aggregate management information storage unit 452 stores aggregate management information indicating which output unit among the output units 481a, 481b,..., 481z is set as an active output unit.
Further, the aggregation management information indicates settings related to hash calculation performed by the hash calculation unit 123. Specifically, the aggregation management information includes frame part specifying information for specifying frame part information, calculation contents information indicating calculation contents of hash calculation, in order for the switching determination unit 422 to determine a physical link that outputs a frame, Each of the output units 481a, 481b,..., 481z has effective physical link number information indicating the number of usable physical links, and operation non-execution information indicating that hash calculation is not performed. Further, the aggregate management information includes frame discard information indicating whether to discard the frame.

  The aggregated destination management information storage unit 453 stores aggregated destination management information indicating a physical link to which a frame is output, similar to the aggregated destination management information storage unit 153 of the first embodiment. Here, the aggregate destination management information is stored in the aggregate destination management information storage unit 453 by configuring aggregate destination management tables 453a and 453b, which will be described later in detail with reference to FIGS. The aggregated destination management information includes physical link information that identifies the physical links of the output units 481a, 481b,..., 481z. Here, the physical link is each port (for example, port # 0,..., Port # 7, etc.) included in the output units 481a, 481b,. Further, in the aggregated destination management information, each hash value calculated by the hash calculation unit 123 is associated with each physical link included in each output unit 481a, 481b,..., 481z indicated by the physical link information. .

  The aggregated destination management information storage unit 453 is configured by a dual port memory. Further, in the physical link specifying information, a part of the address stored in the aggregated destination management information storage unit 453 is associated with each output unit 481a, 481b,. Each output unit 481a, 481b,..., 481z is associated with a physical link.

  The output units 481a, 481b,..., 481z are constituted by different physical links from among the physical links constituting the logical link. The number of physical links constituting each output unit 481a, 481b,..., 481z is the same (for example, 8).

  One of the output units 481a, 481b,..., 481z is an active output unit (for example, output unit 481a) that outputs a frame. Output units (for example, output units 481b,..., 481z) other than those set as the operation system output units are standby system output units that stand by in a state where frames can be output.

  Similarly to the first embodiment, the terminal device 40 is communicably connected to the switch 400, and can display information obtained by communicating with the switch 400. The switch 400 includes a communication unit 140 that can communicate with the terminal device 40. The terminal device 40 can acquire aggregated destination management information and aggregated destination statistical information by communication via the communication unit 140 with the switch 400. The terminal device 40 includes a display unit (not shown) that can display the acquired aggregate destination management information and the aggregate destination statistical information.

  The switch 400 is configured by the plurality of interface cards as in the switch 100 of the first embodiment. Here, an interface card to which a frame is input is referred to as an input card, and an interface card from which a frame is output is referred to as an output card. However, each interface card is functionally identical, Output is possible. That is, the switch 400 is input by an input card that functions as the input unit 110, the distribution unit 420, and the failure detection unit 130, and a plurality of output cards that function as the output units 481a, 481b,. Output the frame to another switch.

  Note that the switching determination unit 422 of this embodiment includes at least one output unit 481a, 481b,..., 481z among the output units 481a, 481b,. 481z is set as the output unit of the standby system, and the output unit set as the output unit of the standby system (for example, the output unit 481z) is set as the output unit of the active system. In response to the switching instruction to switch, the aggregation management information stored in the aggregation management information storage unit 452 is changed to the output unit (for example, the output unit 481a) that is the output unit of the active system that is the target of the switching instruction, and waits. The output unit 481z, which was the system output unit, may be rewritten to be newly set as the active system output unit.

  In this case, the allocation destination determination unit 424 outputs the physical link that outputs the frame in advance as an output unit (for example, output units 481a, 481b,... Other than the output unit 481z). ) And the physical link that outputs the frame with reference to the aggregate management information stored in the aggregate management information storage unit 452, and the physical link that configures the output unit 481z of the standby system Shall be switched to. Thereby, it is possible to realize card redundancy in which a plurality of output units are allocated to the active system and one output unit is allocated to the standby system (1: N).

  FIG. 14 is a diagram illustrating an example of a data structure of an aggregation management table according to the fourth embodiment. The aggregation management table 452 a shown in FIG. 14 is stored in the table storage memory 104. The table storage memory 104 functions as an aggregate management information storage unit 452. The aggregation management table 452a is a table for determining a logical link to which each frame is transmitted, like the aggregation management table 152a shown in FIG. The aggregation management table 452a includes a “V” field, a “LAG number” field, a “SEL” field, an “NH” field, an “HT” field, an “HR” field, an “active AP” field, and a plurality (for example, N−1) “reserve AP” fields (for example, “reserve AP1” field,..., “Reserve AP N−1” field) are provided. Information arranged in the horizontal direction of each field is associated with each other.

  In the SEL field according to the present embodiment, information indicating whether the logical link for transmitting a frame is an active system or a plurality of standby systems is set. Specifically, “0” is set when a frame is transmitted through the working logical link. On the other hand, when a failure occurs in the active logical link and the active logical link is switched to the standby logical link, when the frame is transmitted on the standby logical link, the above “0” is used. By switching, the information is set by rewriting information (for example, a value of 1 to N-1) for specifying a backup logical link used for frame transmission.

  In the plurality of spare AP fields, information indicating the number of ports that can be used in each of the spare logical links, or transmission ports in the spare logical links when hash calculation is not performed based on the NH field. Is set. Specifically, in principle, the number of ports that can be used in the logical link of the standby system at that time is set. When the setting value of the NH field is 1, the value of the HV field (or the address of the aggregate destination management table 453b) of the aggregate destination management table 453a indicating the port to which the frame is transmitted in the backup logical link is directly set. The

  Similar to the aggregation management table 152a, the aggregation management table 452a is stored in the table storage memory 104 in response to an operation input by the administrator of the switch 400. In the aggregation management table 452a, the setting value changes in accordance with the change in the number of usable ports in the logical link of the output unit that is the active system.

  FIG. 15 is a diagram illustrating an example of a data structure of the aggregated destination management table according to the fourth embodiment. The aggregated destination management table 453a illustrated in FIG. 15 is stored in the table storage memory 104. The table storage memory 104 functions as the aggregate destination management information storage unit 453. The aggregated destination management table 453a is a table indicating a destination port that is a communication port to which each frame in the logical link is transmitted, like the aggregated destination management table 153a illustrated in FIG. The aggregate destination management table 453a includes an “HV” field, an “active DP” field, and a plurality (eg, N−1) spare DP fields (eg, “spare DP1” field,..., “Spare DP”. N-1 "field). Information arranged in the horizontal direction of each field is associated with each other.

In the plurality of spare DP fields, information for uniquely identifying a destination port that is a communication port to which a frame is transmitted in each spare logical link is set.
The aggregate destination management table 453 a is stored in the table storage memory 104 in response to an operation input by the administrator of the switch 400.

As described above, according to the fourth embodiment, link aggregation can be configured using many output units, and the reliability of the switch can be improved.
<Modification of Fourth Embodiment>
Next, a modification of the fourth embodiment will be described. Differences from the above-described fourth embodiment will be mainly described, and the same reference numerals are used for similar matters, and descriptions thereof are omitted. The switch of this modification is different in that the working DP and N-1 spare DPs are stored in different addresses in the aggregated destination management table 453b.

  When the working DP and the spare DP are stored in the same address of the aggregate destination management table, it is possible to efficiently use the memory capacity of the table, but when the working system is the active system, the frame input When the aggregated destination management table is always accessed based on the settings, when the setting frame is input and DP setting or change of the non-active system is performed, access from the input packet and the standby system setting are performed. There is a possibility that an access collision (contention) that occurs at the same time as the access of the frame for use occurs. In this case, it is necessary to add an access arbitration control circuit for avoiding this access collision, resulting in a complicated circuit and an increase in the cost of the apparatus.

  FIG. 16 is a diagram illustrating an example of the data structure of the aggregated destination management table in the modification of the fourth embodiment. In this modification, as shown in FIG. 16, the aggregated destination management table 453b is assigned to different addresses by the working DP and the N-1 spare DPs, and a separate area is given to each. As the address of each area, a value obtained by bit-combining the value of the SEL field of the aggregation management table 452a in FIG. 14 and the value of the hash calculation result in FIG.

  Also, the aggregated destination management table 453b in the figure is stored in the dual port memory. For example, in the spare DP, the port # 7 of the standby output unit 182 has a bit combination of the SEL field value “1” and the DP address “7” in the aggregated destination management table 453b. It has become. In the aggregate destination management table 453b, this address associates the relationship between the hash value assigned to the frame and the communication port to which the frame is transmitted.

  The aggregated destination management table 453b illustrated in FIG. 16 is stored in the table storage memory 104. Similar to the aggregated destination management table 453a, the aggregated destination management table 453b is a table indicating a destination port that is a communication port to which each frame in the logical link is transmitted. The aggregated destination management table 453b stores information for uniquely identifying the destination port in the working or protection logical link associated with the hash value of the frame at the above address. The aggregate destination management table 453 b is stored in the table storage memory 104 in response to an operation input by the administrator of the switch 400.

  As described above, according to the present modification, in the aggregated destination management table 453b, the active DP and the plurality of spare DPs are assigned to different areas, respectively, so that the setting change and registration on the non-operating system side can be performed. Can be performed without causing access collision.

[Fifth Embodiment]
Next, a fifth embodiment will be described. Here, the difference from the second embodiment and the fourth embodiment will be mainly described, and the same reference numerals are used for the same matters and the description is omitted.

  The fifth embodiment has no output unit, does not actually output the frame, performs only the distribution of the frame, and acquires only the statistical information of the physical link to which the frame is distributed. This is different from the above embodiment.

Below, the distribution part 520 in this Embodiment is demonstrated. FIG. 17 is a block diagram illustrating functions of the distribution unit according to the fifth embodiment.
The distribution unit 520 of this embodiment includes a frame output from each physical link in addition to the flow destination determination unit 121, the switching determination unit 422, the hash calculation unit 123, the distribution destination determination unit 424, and the frame discard unit 125. Statistical information writing unit 526 is included. Further, the switch (not shown) of the present embodiment includes an input unit (not shown), a distribution unit 520, a failure detection unit 130, a communication unit (not shown), a flow destination management information storage unit 151, an aggregate management information storage unit 452, and an aggregate destination management. In addition to the information storage unit 453, an aggregated destination statistical information storage unit 554 is provided to store a total result of the number of frames output from each physical link.

  On the other hand, unlike the fourth embodiment, the switch of the present embodiment does not have the output units 481a, 481b,. Although this output unit does not actually exist, it is assumed that it has a specification equivalent to that of an actual switch for testing (for example, having eight ports to which a physical link is connected). Only set on.

As in the fourth embodiment, the input unit receives a frame transferred to a communication device such as another switch and a terminal device by the switch of the present embodiment.
As in the fourth embodiment, the allocating unit 520 refers to the aggregate destination management information stored as the aggregate destination management table in the aggregate destination management information storage unit 453, and sets a plurality of physical links that output frames. Is set to a physical link that constitutes one of the output units that does not exist, and the physical link that outputs a frame is switched to a physical link that constitutes another output unit in response to a switching instruction.

  When it is assumed that a failure has occurred in communication between the switch of this embodiment and another switch via a logical link, the switching instruction is distributed by the failure detection unit 130 based on the detection of the occurrence of the failure. A switching instruction is output to the switching determination unit 422 of the unit 520. Based on the switching by the allocating unit 520, the active output unit is switched from the output unit that is the active output unit that is currently outputting the frame to one of the standby output units. After this switching, the number of frames output from the output unit of the standby system is totaled accordingly.

  Also, the distribution unit 520 switches the active output unit based on the number of usable physical links. When the number of physical links indicated by the effective physical link information of the active output unit is less than the band indicated by the band information, the allocating unit 520 selects one of the other standby output units. Switch to the active output section. Band information indicating a band to be secured for transmitting the frame is set in the frame transmitted by the switch in accordance with the transmission destination. This band information is stored in a storage unit (not shown) of the switch.

  As in the fourth embodiment, the flow destination determination unit 121 refers to the flow destination management information stored in the flow destination management information storage unit 151 and configures the physical link from which the frame is output as a logical link. Or one of the physical links (not shown) other than the physical links constituting the logical link.

  Similar to the fourth embodiment, the switching determination unit 422 sets the output unit set as the active output unit as the standby output unit when the switching instruction from the failure detection unit 130 is detected. In addition, in accordance with a switching instruction to switch the active output unit by setting at least one output unit among the output units set as the standby output unit to the active output unit, the integrated management information storage unit 452 The integrated management information stored in is replaced with the output unit that was the active output unit, and it is a standby output unit, and one of the output units that are the target of switching is newly operated Set to the output section of the system. At this time, the switching determination unit 422 rewrites the aggregate management information to reflect the setting. Based on this, the statistical information writing unit 526 that refers to the aggregate management information determines a physical link to which a frame is output from among the output units of the standby system.

  The switching determination unit 422 also causes the hash calculation unit 123 to perform hash calculation with reference to the aggregation management information, as in the fourth embodiment. At this time, the switching determination unit 422 extracts frame part information from the entire frame based on the frame part specifying information, and causes the hash calculation unit 123 to perform hash calculation using the extracted frame part information. Also, the switching determination unit 422 causes the hash calculation unit 123 to perform hash calculation based on the calculation content information. Furthermore, when the operation non-execution information is detected, the switching determination unit 422 determines a physical link that outputs a frame without causing the hash calculation unit 123 to perform hash calculation.

  The hash calculation unit 123 calculates a hash value by using a hash function that can take the same number of types of values as the number of physical links included in each output unit for the frame part information constituting a part of the frame.

  The distribution destination determination unit 424 sets a physical link that outputs a frame in advance as a physical link that constitutes an output unit that is set as an output unit of the active system, and is stored in the aggregation management information storage unit 452. With reference to the aggregation management information, the physical link that outputs the frame is switched to the physical link that forms the output unit of the standby system.

  Here, the distribution destination determination unit 424 refers to the aggregation management information, switches the active output unit to any one of the standby output units, and refers to the aggregate destination management information to determine the hash calculation unit 123. The physical link to which the frame is output is determined on the basis of the hash value obtained by calculating, and the determination result is output to the statistical information writing unit 526. Based on this, the statistical information writing unit 526 aggregates the number of frames to be output from the determined physical link.

  As in the fourth embodiment, the frame discard unit 125 discards the frame when the frame discard information included in the aggregate destination management information indicates that the frame is to be discarded. Thereby, when performing the test which transmits a frame only to a specific transmission destination or only to a specific transmission destination, the frame to be output can be limited.

  The statistical information writing unit 526 acquires the result of determination by the distribution destination determining unit 424, and stores the total number of frames output from each physical link in the aggregate destination statistical information storage unit 554 as aggregated destination statistical information. Write.

  As in the fourth embodiment, the failure detection unit 130 detects the occurrence of a failure in the physical link constituting the active output unit 181 and outputs a switching instruction when the occurrence of the failure is detected.

  As in the fourth embodiment, the flow destination management information storage unit 151 uses a physical link that outputs a frame as a physical link that constitutes a logical link, or a physical link other than a physical link that constitutes a logical link. The flow destination management information indicating whether or not to be stored is stored.

The aggregate management information storage unit 452 stores aggregate management information indicating which output unit of the output units is set as the output unit of the active system, as in the fourth embodiment.
Further, the aggregation management information indicates the setting related to the hash calculation performed by the hash calculation unit 123, as in the fourth embodiment. Specifically, the aggregation management information includes frame part specifying information for specifying frame part information, calculation contents information indicating calculation contents of hash calculation, in order for the switching determination unit 422 to determine a physical link that outputs a frame, It has effective physical link number information indicating the number of usable physical links in each of the plurality of output units, and operation non-execution information indicating that hash calculation is not performed. Further, the aggregate management information includes frame discard information indicating whether to discard the frame.

  The aggregated destination management information storage unit 453 stores aggregated destination management information indicating a physical link to which a frame is output, as in the fourth embodiment. Here, the aggregated destination management information constitutes the aggregated destination management tables 453a and 453b and is stored in the aggregated destination management information storage unit 453. The aggregated destination management information includes physical link information that identifies the physical link of each output unit. The physical link is each port included in each output unit. Further, in the aggregated destination management information, each hash value calculated by the hash calculation unit 123 is associated with each physical link indicated by the physical link information.

  The aggregated destination management information storage unit 453 is configured by a dual port memory as in the fourth embodiment. In the physical link specifying information, a part of the address stored in the aggregated destination management information storage unit 453 is associated with each output unit, and the other part of the address is associated with the physical link. .

  Similar to the aggregate destination statistical information storage unit 254 of the second embodiment, the aggregate destination statistical information storage unit 554 stores the aggregate destination statistical information that is the aggregated result of the number of frames output from each physical link of each output unit. Remember. Further, the aggregated destination statistical information storage unit 554 is configured by a dual port memory, like the aggregated destination management information storage unit 453. In addition, in the aggregate destination statistical information, a part of the address stored in the aggregate destination statistical information storage unit 554 is associated with each output unit, and the other part of the address is associated with the physical link.

  The output unit is set to be composed of a part of different physical links among the physical links constituting the logical link. It is assumed that the number of physical links constituting each output unit is the same (for example, 8). One output unit of the plurality of output units is an active output unit that outputs a frame. The output units other than those set as the active output unit are standby output units that stand by in a state where frames can be output.

  As in the second embodiment, the communication unit (not shown) includes the aggregate destination management information stored in the aggregate destination management information storage unit 453 and the aggregate destination statistics stored in the aggregate destination statistical information storage unit 554. Information is output to a terminal device (not shown). Similar to the terminal device of the fourth embodiment, the terminal device is communicably connected to a communication unit included in the switch of the present embodiment, and can display information obtained by communicating with the communication unit. The terminal device can acquire aggregated destination management information and aggregated destination statistical information by communication via the communication unit. The terminal device includes a display unit (not shown) that can display the acquired aggregate destination management information and aggregate destination statistical information.

  FIG. 18 is a diagram illustrating an example of a data structure of an aggregate destination statistics table according to the fifth embodiment. In this embodiment, as shown in FIG. 18, the aggregated destination statistics table 554a is assigned to different addresses by the working DP and the N-1 spare DPs, and a separate area is given to each.

  Also, the aggregated destination statistics table 554a in the figure is stored in the dual port memory, like the aggregated destination statistics table 254a in FIG. For example, in the working DP, the port # 7 of the working output unit (the eighth line from the top in the aggregate destination statistics table 554a) has the value “0” in the SEL field and the DP address “7” in the aggregate destination statistics table 554a. Are bit-coupled to be “0x07” in hexadecimal notation. In the aggregate destination statistics table 554a, this address associates the relationship between the communication port to which the frame is transmitted and the number of frames to be transmitted from the communication port.

  The aggregated destination statistics table 554a illustrated in FIG. 18 is stored in the table storage memory 104. The table storage memory 104 functions as the aggregate destination statistical information storage unit 554. The aggregated destination statistics table 554a is a table that indicates a totaled result of the number of frames transmitted from the communication port. The aggregated destination statistics table 554a stores information indicating the number of frames transmitted from the destination port in the working or protection logical link, which is associated with the frame hash value at the above address. The aggregated destination statistics table 554a is stored in the table storage memory 104 in accordance with the writing of the aggregation results by the statistics information writing unit 526.

  As described above, according to the fifth embodiment, the information indicating the number of frames transmitted from each communication port is stored in the aggregate destination statistics table 554a, so that the frame distribution function of the switch 100 can be obtained. When performing the test, the output unit can be omitted, and the distribution result can be easily obtained.

Further, since no output side interface card is required, the test can be performed with only one interface card.
[Sixth Embodiment]
Next, a sixth embodiment will be described. Differences from the first embodiment will be mainly described, and the same reference numerals are used for the same matters, and descriptions thereof are omitted.

  The sixth embodiment is different from the first embodiment in that a frame can be transmitted not only by a unicast flow but also by a multicast flow in a logical link using link aggregation.

Hereinafter, the switch 600 in the present embodiment will be described. FIG. 19 is a block diagram illustrating functions of a switch according to the sixth embodiment.
The switch 600 according to this embodiment includes an input unit 110, a distribution unit, and a logical unit having a redundant configuration based on link aggregation and a frame for multicast flow transmission to a physical link that does not have a redundant configuration. 620, failure detection unit 130, communication unit 140, flow destination management information storage unit 651, aggregated multicast management information storage unit 692, aggregated multicast destination management information storage unit 693, multicast destination management information storage unit 695, two redundant system outputs Part 681a, 681b and a plurality of independent output parts 682x,. In addition, the distribution unit 620 includes a flow destination determination unit 621. The multicast distribution unit 670 includes a multicast switching determination unit 672, a hash calculation unit 673, a multicast destination determination unit 674, and a multicast distribution destination determination unit 675.

  Although description is omitted in the present embodiment, the switch 600 includes the aggregation management information storage unit 152, the aggregation destination management information storage unit 153, and the flow destination determination unit 121 in FIG. 5 of the first embodiment. It has a distribution unit 120 having a switching determination unit 122, a hash calculation unit 123, and a distribution destination determination unit 124, and uses a logical link composed of a redundant system output unit 681a and a redundant system output unit 681b, Can be transferred.

As in the first embodiment, the input unit 110 receives a frame transferred to a communication device such as another switch and a terminal device by the switch 600 of the present embodiment.
The flow destination determination unit 621 included in the distribution unit 620 according to the present embodiment refers to the flow destination management information stored in the flow destination management information storage unit 651 and determines the frame input by the input unit 110 as a redundant Output by unicast using only logical links configured by system output units 681a and 681b, or independent system output configured by only physical links without redundant configuration in addition to redundant system output units 681a and 681b .. 682x,... Are also determined for multicast output.

  Here, when the input frame is output by multicast, 1 is normally set to the most significant bit of the MAC address (see FIG. 4) of the frame. Accordingly, in the flow destination determination unit 621 according to the present embodiment, when the most significant bit is 1, an address in which any arbitrary most significant bit is 1 is registered as a multicast address in the flow destination management table 651a. The destination information of the multicast address is acquired from the MAC address of the frame that has been set.

  Further, when the destination port is a logical link (LAG), by setting 1 in the L field associated with the destination MAC address of the frame transmitted by the logical link in the flow destination management table 651a, the logical destination is set. A link can be specified. Accordingly, when 1 is set in the L field associated with the destination MAC address of the frame, the flow destination determination unit 621 determines the destination of the frame as the designated logical link.

  Note that the information on the frame side to be associated with the address of the flow destination management table 651a is not limited to the destination MAC address, and a value indicated by the VLAN tag (see FIG. 4) may be used.

  Further, when the destination MAC address or the VLAN tag is used for association with the address of the flow destination management table 651a, the number of bits of the address on the flow destination management table 651a side becomes very large. Based on this, the memory capacity required for the flow destination management table 651a increases as in the first embodiment. On the other hand, as a memory for storing the flow destination management table 651a, CAM may be used instead of general SRAM and DRAM.

  The distribution unit 620 omits the description, but when the frame is output by unicast, it is stored in the aggregated destination management information storage unit (not shown) as with the distribution unit 120 of the first embodiment. With reference to the aggregate destination management information stored as the aggregate destination management table, a physical link that outputs a frame is set, and a physical link that outputs a frame is switched according to a switching instruction. In the switching instruction, when a failure occurs in communication between the switch 600 and another switch through a logical link, the failure detection unit 130 detects the occurrence of the failure. Then, the failure detection unit 130 outputs a switching instruction to the switching determination unit (not shown) of the distribution unit 620 based on the detection of the occurrence of the failure. In this manner, the active output unit is switched to one of the standby output units.

  When the flow destination determination unit 621 determines that the frame is to be output by multicast, the multicast distribution unit 670 refers to the multicast destination management information and outputs the physical link to which the frame input by the input unit 110 is output. As the physical link, a physical link that outputs a frame is determined from the physical link that configures the logical link and the physical link that does not configure the logical link.

  When the multicast switching determination unit 672 detects the switching instruction from the failure detection unit 130, the multicast switching determination unit 672 sets the redundant output unit set as the active output unit as the standby redundant output unit and sets the standby system output unit. Stored in the aggregated multicast management information storage unit 692 in response to a switching instruction to switch the redundant system output unit of the active system by setting the redundant system output unit set as the redundant system output unit to the redundant system output unit of the active system The redundant multicast output unit (ie, the redundant output unit 681a) that is the standby redundant output unit instead of the redundant output unit (eg, the redundant output unit 681a) that is the active redundant output unit. For example, the redundant output unit 681b) is newly set as the active redundant output unit. Specifically, at this time, the multicast switching determination unit 672 rewrites the aggregated multicast management information to reflect the setting. Based on this, the multicast destination determining unit 674 that refers to the aggregated multicast management information switches the physical link to which the frame is output to the standby redundant output unit 681b.

  Also, the multicast switching determination unit 672 refers to the multicast aggregation management information and causes the hash calculation unit 673 to perform hash calculation. At this time, the multicast switching determination unit 672 extracts frame part information from the entire frame based on the frame part specifying information, and causes the hash calculation unit 673 to perform hash calculation using the extracted frame part information. Also, the multicast switching determination unit 672 causes the hash calculation unit 673 to perform hash calculation based on the calculation content information. Further, when multicast non-execution information is detected, the multicast switching determination unit 672 determines a physical link that outputs a frame without causing the hash calculation unit 673 to perform hash calculation.

  The hash calculation unit 673 uses the same type as the number of physical links included in each output unit such as the redundant system output units 681a and 681b and the independent system output units 682x,. The hash value is calculated using a hash function that can take a numeric value.

  The multicast destination determination unit 674 refers to the aggregated multicast information stored in the aggregated multicast management information storage unit 692 and selects the pattern indicated by the working physical link information or selects the pattern indicated by the backup physical link information. A switching decision is made.

  Here, the multicast destination determination unit 674 sets a logical link for outputting a frame in advance to the redundant output unit (for example, the redundant output unit 681a) set as the output unit of the active system. When a failure occurs in the physical link of the redundant output unit of the active system, the multicast destination determination unit 674 refers to the aggregated multicast destination management information stored in the aggregated multicast destination management information storage unit 693. From the redundant output unit (redundant output unit 681a) set as the output unit of the above-mentioned active system to the physical link that outputs the frame, the redundant output unit set as the standby output unit (for example, To the redundant output unit 681b).

  That is, the multicast destination determination unit 674 refers to the aggregated multicast destination management information stored in the aggregated multicast destination management information storage unit 693 and, based on the result of the switching determination, determines the working physical link information or the spare physical link information. Based on the pattern and the hash value obtained by calculation by the hash calculation unit 673, the pattern of the physical link from which the frame is output is determined.

  Thus, the multicast destination determination unit 674 refers to the aggregated multicast management information, switches the active redundant output unit constituting the logical link to the standby redundant output unit, and refers to the aggregated destination management information. Then, based on the hash value obtained by the calculation by the hash calculation unit 673, the physical link to which the frame is output is determined.

  The multicast distribution destination determination unit 675 refers to the multicast destination management information stored in the multicast destination management information storage unit 695, and based on the hash value obtained by the hash calculation unit 673 calculating the frame, Determine the physical link to be output.

The failure detection unit 130 detects the occurrence of a failure in the physical link constituting the redundant output unit 681a, and outputs a switching instruction when the occurrence of the failure is detected.
The flow destination management information storage unit 651 stores the flow destination management information indicating the transmission destination of the frame and indicating whether the frame is output by unicast or multicast.

  The aggregated multicast management information storage unit 692 indicates from which physical link the frame is output from among the physical links constituting the redundant output units 681a, 681b and the independent output units 682x,. The aggregate multicast management information shown is stored.

  Further, the aggregated multicast management information indicates settings related to hash calculation performed by the hash calculation unit 673. Specifically, the aggregated multicast management information indicates the frame part specifying information for specifying the frame part information and the calculation content of the hash calculation so that the multicast switching determining unit 672 determines the physical link for outputting the frame by multicast. It has calculation content information, effective physical link number information indicating the number of usable physical links in each of the redundant output units 681a and 681b, and operation non-execution information indicating that hash calculation is not performed.

  The aggregated multicast destination management information storage unit 693 stores aggregated multicast destination management information. Here, the aggregated multicast destination management information is stored in the aggregated multicast destination management information storage unit 693 by configuring an aggregated multicast destination management table 693a, which will be described in detail later with reference to FIG. The aggregated multicast destination management information includes physical link information that identifies the physical links of the respective output units such as the redundant system output units 681a and 681b, the independent system output units 682x, and so on. Here, the physical link is each port (for example, port # 0,..., Port # 7) included in the output unit. Furthermore, the aggregated multicast destination management information is associated with each hash value calculated by the hash calculation unit 673 and each pattern indicated by the working physical link information, and each hash value calculated by the hash calculation unit 673 Are associated with each pattern indicated by the spare physical link information.

The aggregated multicast destination management information storage unit 693 is configured by a dual port memory, like the aggregated destination management information storage unit 153 of the first embodiment.
The multicast destination management information storage unit 695 stores multicast destination management information indicating a physical link from which a frame is output among physical links that constitute a logical link and physical links that do not constitute a logical link.

  The multicast destination management information includes a plurality of working physical links indicating a pattern including a working physical link of the redundant output units 681a and 681b and a non-redundant physical link of the independent output units 682x,. A plurality of pieces of information indicating a combination pattern including information and a spare physical link of the redundant output units 681a and 681b and a non-redundant physical link of the independent output units 682x,. Spare physical link information. In the multicast destination management information, the pattern determined by the multicast destination determination unit 674 is associated with each physical link.

  The redundant output units 681a and 681b are constituted by physical links that constitute a logical link. The redundant output units 681a and 681b are composed of a working physical link that is a physical link that outputs a frame, and a backup physical link that is a physical link that stands by in a state where the frame can be output. The independent output units 682x,... Are composed of non-redundant physical links that are physical links that do not constitute a logical link. The number of physical links constituting each output unit is the same (for example, 8).

  One of the redundant output units 681a and 681b is an operational output unit (for example, a redundant output unit 681a) that outputs a frame. The other output unit (for example, the redundant system output unit 681b) of the redundant system output units 681a and 681b is a standby system output unit that waits in a state in which a frame can be output. The independent output units 682x,... Are configured from a plurality of physical links, but do not form a logical link and function independently.

  Redundant system output units 681a, 681b and independent system output units 682x,... Are determined by multicast distribution destination determination unit 675 as communication ports of each output unit as destination ports for sending frames according to multicast destination management information. Then, the frame is copied and sent out from the determined destination port.

  Similarly to the first embodiment, the terminal device 40 is communicably connected to the switch 600 and can display information obtained by communicating with the switch 600. The switch 600 includes a communication unit 140 that can communicate with the terminal device 40. The terminal device 40 can acquire aggregated destination management information and aggregated destination statistical information by communication with the switch 600 via the communication unit 140. The terminal device 40 includes a display unit (not shown) that can display the acquired aggregate destination management information and the aggregate destination statistical information.

  Further, the switch 600 is configured by the plurality of interface cards as in the case of the switch 100 of the first embodiment. Here, an interface card to which a frame is input is referred to as an input card, and an interface card from which a frame is output is referred to as an output card. However, each interface card is functionally identical, Output is possible. That is, the switch 600 includes an input unit 110, a distribution unit 620, a multicast distribution unit 670, an input card that functions as the failure detection unit 130, redundant output units 681a and 681b, independent output units 682x,. The input frame is output to another switch or the like by a plurality of output cards each functioning as an output unit.

  FIG. 20 is a diagram illustrating an example of a data structure of a flow destination management table according to the sixth embodiment. A flow destination management table 651a illustrated in FIG. 20 is stored in the table storage memory 104. The table storage memory 104 functions as the flow destination management information storage unit 651. The flow destination management table 651a indicates whether each frame is output by unicast or multicast, and indicates whether a link that is a transmission destination of each frame constitutes a logical link. It is a table. In the flow destination management table 651a, an “L” field indicating whether or not the destination port to which the frame is transmitted constitutes a logical link, and whether the frame is output by unicast or multicast. An “M” field and a “destination” field indicating a destination to which the frame is output are provided. Information arranged in the horizontal direction of each field is associated with each other.

  Information indicating whether the destination port of the frame constitutes a logical link is set in the L field. Specifically, when the destination port of the frame is not a logical link, “0” is set. On the other hand, when the destination port of the frame is a logical link, “1” is set.

  Information indicating whether the frame is output by unicast or multicast is set in the M field. Specifically, when the frame is output by unicast, “0” is set. On the other hand, when the frame is output by multicast, “1” is set.

  In the destination field, when the destination of the frame is a logical link, a LAG number described later in FIG. 21 is set. On the other hand, when the destination port of the frame is not a logical link, information indicating the destination card name indicating the interface card that transmits the frame and the port number is set.

The flow destination management table 651a is stored in the table storage memory 104 in response to an operation input by the administrator of the switch 600.
FIG. 21 is a diagram illustrating an example of a data structure of the aggregated multicast management table according to the sixth embodiment. The aggregated multicast management table 692a shown in FIG. 21 is stored in the table storage memory 104. The table storage memory 104 functions as the aggregated multicast management information storage unit 692. The aggregated multicast management table 692a is a table for determining a logical link to which each frame is transmitted in the multicast flow. The aggregated multicast management table 692a is provided with a “LAG number” field, “SEL” field, “NH” field, “HT” field, “HR” field, “working AP” field, and “reserve AP” field. Yes. Information arranged in the horizontal direction of each field is associated with each other.

  In the LAG number field, a LAG number for allocating link aggregation destinations in the multicast flow is set. According to the LAG number, it is determined which of the link aggregation distribution patterns preset in the aggregation multicast management table 692a is to be allocated.

  In the SEL (Selector) field, information indicating whether a logical link for transmitting a frame is an active system or a standby system is set. Specifically, “0” is set when a frame is transmitted through the logical link of the active redundant output unit (for example, the redundant output unit 681a). On the other hand, when a failure occurs in the working logical link and switching from the working logical link to the standby logical link, the logical link of the redundant redundant output unit (for example, redundant redundant output unit 681b) is used. When a frame is transmitted, it is set by rewriting from “0” to “1”.

  In the NH (No Hash) field, information indicating whether or not hash calculation is performed in frame allocation is set. Specifically, “0” is set when hash calculation is performed in the distribution of frames. On the other hand, when hash calculation is not performed in the distribution of frames, “1” is set.

  In the HT (Hash Target) field, a value to be subjected to hash calculation when hash calculation is performed is set. Specifically, “0” is set when the value to be subjected to hash calculation is the MAC address of the frame. Also, “1” is set when the value for hash calculation is the VLAN ID of the frame. Also, “2” is set when the value targeted for hash calculation is an IP address.

  Information indicating a rule for hash calculation is set in an HR (Hash Rule) field. Specifically, “0” is set when hash calculation is performed using a remainder obtained by dividing a target value by the number of Active Ports described later as a hash value. When hash calculation is performed using a remainder obtained by dividing a target value by a generator polynomial as a hash value, “1” is set.

  The active AP (Active Port) field indicates the number of ports that can be used in the logical link of the active redundant output unit, or the transmission port in the active logical link when hash calculation is not performed based on the NH field. Information is set. Specifically, in principle, the number of ports that can be used in the working logical link at that time is set. When the setting value of the NH field is 1, the value of the HV field of the aggregated multicast destination management table 693a indicating the port to which the frame is transmitted in the working logical link is directly set.

  In the spare AP field, information indicating the number of ports that can be used in the logical link of the redundant redundant output unit or information indicating the transmission port in the standby logical link when hash calculation is not performed is set based on the NH field. The Specifically, in principle, the number of ports that can be used in the backup logical link at that time is set. When the setting value of the NH field is 1, the value of the HV field of the aggregated multicast destination management table 693a indicating the port to which the frame is transmitted in the backup logical link is directly set.

  The aggregated multicast management table 692a is stored in the table storage memory 104 in response to an operation input by the administrator of the switch 600, like the aggregated management table 152a. In the aggregated multicast management table 692a, the set value changes according to the change in the number of usable ports in the logical link of the redundant output unit that is the active system.

  FIG. 22 is a diagram illustrating an example of a data structure of the aggregated multicast destination management table according to the sixth embodiment. The aggregated multicast destination management table 693 a shown in FIG. 22 is stored in the table storage memory 104. The table storage memory 104 functions as the aggregated multicast destination management information storage unit 693. The aggregated multicast destination management table 693a is a table showing a pattern of destination ports that are communication ports to which each frame is transmitted in the multicast flow defined in the multicast destination management table 695a (FIG. 23). In the aggregated multicast destination management table 693a, the multicast flow using the “HV” field indicating the correspondence between the hash value assigned to the frame and the pattern of the destination port to which the frame is sent, and the active redundant output unit In addition, a “working MID” field indicating a destination port pattern and a “backup MID” field indicating a destination port pattern in a multicast flow using a standby redundant output unit are provided. Information arranged in the horizontal direction of each field is associated with each other.

In the HV field (Hash Value), a value indicating the correspondence between the hash value assigned to the frame and the pattern of the communication port to which the frame is transmitted is set.
In the working MID (Multicast ID) field, information for uniquely identifying the pattern of the destination port to which the frame is transmitted in the multicast flow using the logical link of the working redundant output unit is set.

  In the spare MID field, information for uniquely identifying a destination port pattern to which a frame is transmitted in a multicast flow using the logical link of the redundant redundant output unit is set.

  A destination port pattern to which a frame is transmitted in these multicast flows and information for uniquely identifying the pattern are shown in the multicast destination management table 695a shown in FIG.

Aggregated multicast destination management table 693 a is stored in table storage memory 104 in response to an operation input by the administrator of switch 600.
FIG. 23 is a diagram illustrating a data structure example of a multicast destination management table according to the sixth embodiment. A multicast destination management table 695 a shown in FIG. 23 is stored in the table storage memory 104. The table storage memory 104 functions as a multicast destination management information storage unit 695. The multicast destination management table 695a is a table showing a destination port pattern of each frame output by multicast. The multicast destination management table 695a includes an “MID” field indicating a destination port pattern to which the frame is transmitted and an “A-0” to “Z-7” field (the destination port to which the frame is transmitted in the multicast flow) ( Hereinafter, the destination port field is provided. Information arranged in the horizontal direction of each field is associated with each other. Here, the destination port field is provided so as to correspond to the communication port of each output unit such as the redundant system output units 681a and 681b, the independent system output units 682x,.

  In the MID field, a destination port pattern to which a frame is transmitted in a multicast flow and information for uniquely identifying the pattern are set. Based on the information shown in the working MID field and the backup MID field shown in the aggregated multicast destination management table 693a, the multicast distribution destination determination unit 675 has the information shown in the MID field of the multicast destination management table 695a. The destination port pattern to which the frame is transmitted can be specified by referring to the destination port pattern.

  In the destination port field, in the destination port pattern specified by the information in the MID field, the communication port of each output unit such as the redundant output units 681a and 681b, the independent output units 682x,. Information indicating whether or not the destination port is to be set is set. Specifically, if the communication port indicated in the destination port field is not the destination port, “0” is set. On the other hand, when the communication port indicated in the destination port field is the destination port, “1” is set.

The multicast destination management table 695a is stored in the table storage memory 104 in response to an operation input by the administrator of the switch 600.
As a result, the multicast distribution unit 670 can perform frame transfer by multicast flow for both the logical link and the physical link in a communication system in which a logical link using link aggregation and a physical link having no redundant configuration are used in combination. become.

  As described above, according to the sixth embodiment, it is possible to construct a highly reliable communication system using logical links using link aggregation regardless of unicast flows and multicast flows.

  In the present embodiment, the case where the layer 2 switch is used as the communication device has been described. However, another type of communication device having a frame transfer function may be used. For example, a router or the like that can also process higher layers than the data link layer may be used.

  Although the communication apparatus, communication system, and communication method of the present invention have been described based on the illustrated embodiments, the above description merely shows the principle of the present invention. The present invention is not limited to the exact configurations and applications shown and described above, and many variations and modifications are possible to those skilled in the art, and all corresponding variations and equivalents are The structure of each part can be replaced with any structure having a similar function. Moreover, other arbitrary structures and processes may be added to the present invention. Further, the present invention may be a combination of any two or more configurations (features) of the above-described embodiments.

Regarding the above embodiment, the following additional notes are disclosed.
(Supplementary Note 1) In a communication device that transfers a frame using a logical link configured by aggregating a plurality of physical links,
An input means for inputting a frame;
Aggregate destination management information storage means for storing aggregate destination management information indicating the physical link from which the frame is output;
Referring to the aggregated destination management information, the physical link from which the frame input by the input unit is output is determined to be any one of the physical links constituting the logical link. Minute means,
First output means comprising a part of the physical links of the physical links constituting the logical link;
Second output means comprising a part or all of the physical links of the physical links other than the physical links constituting the first output means of the physical links constituting the logical link. When,
Have
The aggregated destination management information includes first physical link information that identifies the physical link of the first output unit, and second physical link information that identifies the physical link of the second output unit. And
The distribution means includes
A first state in which the physical link from which the frame is output with reference to the first physical link information is determined as the physical link constituting the first output means, and the second physical link information The physical link from which the frame is output can be switched to a second state in which the physical link constituting the second output means is determined, and
A communication apparatus that switches from the first state to the second state in response to a switching instruction.

(Additional remark 2) The management information which shows whether the said frame is output from the said physical link which comprises the said 2nd output means from the said physical link which comprises the said 1st output means is memorize | stored A management information storage means;
The number of physical links constituting the first output means and the number of physical links constituting the second output means are the same;
The sorting means hashes that can take the same number of types of values as the number of physical links of the first output means and the second output means in the frame part information constituting a part of the frame. A hash calculation means for calculating a hash value using a function;
In the aggregated destination management information, each hash value calculated by the hash calculation unit is associated with each physical link indicated by the first physical link information, and is calculated by the hash calculation unit. Each hash value is associated with each physical link indicated by the second physical link information,
The distribution means includes
In response to the switching instruction, switching determination means for rewriting from indicating the first state to indicating the second state;
With reference to the aggregation management information, the hash value obtained by the calculation by the hash calculation means with reference to the aggregation destination management information is referred to while switching from the first state to the second state. A destination determination means for determining the physical link from which the frame is output,
The communication apparatus according to appendix 1, characterized by comprising:

(Additional remark 3) The said aggregation management information has the frame part specific information which specifies the said frame part information,
The switching determination unit extracts the frame part information from the entire frame based on the frame part specifying information, and causes the hash calculation unit to perform the hash calculation using the extracted frame part information. The communication apparatus according to supplementary note 2, which is characterized.

(Additional remark 4) The said aggregation management information has the calculation content information which shows the calculation content of the said hash calculation,
The communication apparatus according to claim 2, wherein the switching determination unit causes the hash calculation unit to perform the hash calculation based on the calculation content information.

(Supplementary Note 5) The aggregation management information includes operation non-execution information indicating that the hash calculation is not performed.
The switching determination unit determines the physical link that outputs the frame without performing the hash calculation in the hash calculation unit when the calculation non-execution information is detected. The communication device described.

(Supplementary Note 6) The communication apparatus according to Supplementary Note 1, wherein the aggregated destination management information storage unit is configured by a dual port memory.
(Additional remark 7) The said aggregation destination management information has the physical link specific information which specifies the said physical link,
In the physical link specifying information, a part of the address stored in the aggregated destination management information storage unit is associated with the first output unit and the second output unit, and the other part of the address Is associated with the physical link. The communication apparatus according to appendix 1.

(Supplementary Note 8) The aggregate management information includes effective physical link number information indicating the number of usable physical links in each of the first output unit and the second output unit,
The communication apparatus according to claim 2, wherein the distribution unit switches from the first state to the second state based on the number of usable physical links.

(Supplementary note 9) In the frame, band information indicating a band to be secured is set for each transmission destination of the frame,
When the number of the physical links indicated by the effective physical link information of the first output means is less than the band indicated by the band information, the allocating means starts from the first state to the first state. 9. The communication device according to appendix 8, wherein the communication device is switched to a state of 2.

(Supplementary Note 10) The aggregation management information includes frame discard information indicating whether to discard the frame,
The communication according to claim 1, wherein the distribution unit includes a frame discard unit that discards the frame when the frame discard information included in the aggregated destination management information indicates that the frame is to be discarded. apparatus.

(Additional remark 11) It can communicate using the said logical link one or more,
A plurality of output cards having a plurality of the physical links;
The logical link can be configured with the physical link that configures one of the output cards, and can be configured with the physical link that configures a plurality of the output cards,
The allocating means can set whether each logical link is constituted by the physical link constituting one of the output cards or the physical link constituting a plurality of the output cards. The communication apparatus according to supplementary note 1, characterized by the above.

(Additional remark 12) It has an input card which has the above-mentioned input means, and an output card which has the above-mentioned 1st output means and the above-mentioned 2nd output means,
The communication apparatus according to appendix 1, wherein the input card includes the sorting unit.

(Supplementary note 13) Flow destination management information indicating whether the physical link from which the frame is output is the physical link constituting the logical link or a physical link other than the physical link constituting the logical link Flow destination management information storage means for storing
The distribution means includes
With reference to the flow destination management information stored in the flow destination management information storage means, the physical link from which the frame is output is configured as the physical link constituting the logical link or the logical link. Having a flow destination determination unit that determines one of the physical links other than the physical link,
The communication apparatus according to claim 1, wherein the physical port to which the frame is output is determined based on the determination by the flow destination determination unit.

(Additional remark 14) While detecting the generation | occurrence | production of the failure of the said physical link which comprises the said 1st output means, when detecting the generation | occurrence | production of the said failure, it has a failure detection means which outputs the said switching instruction | indication,
When the switching determination unit detects the switching instruction by the failure detection unit, the switching management unit rewrites the aggregate management information from indicating the first state to indicating the second state. The communication apparatus according to Supplementary Note 2.

(Additional remark 15) It has the aggregate management information storage means which memorize | stores the aggregate management information which shows the setting regarding the said hash calculation,
The communication apparatus according to appendix 3, wherein the switching determination unit causes the hash calculation unit to perform the hash calculation with reference to the aggregation management information.

(Supplementary Note 16) The number of physical links constituting the first output means is the same as the number of physical links constituting the second output means,
The hash calculation means is a hash that can take the value of the same number of types as the number of physical links of the first output means and the second output means in the frame part information constituting a part of the frame. The communication apparatus according to appendix 2, wherein a hash value is calculated using a function.

(Additional remark 17) It has the aggregate destination statistical information storage means which memorize | stores the aggregate destination statistical information which is the total result of the number of the said frames output from each said physical link,
The allocating means outputs the frame based on the hash value obtained by the hash calculation means referring to the aggregation management information stored in the aggregation management information storage means. And a statistical information writing unit that determines a physical link and writes a totaling result of the determined number of frames output from each physical link to the aggregated destination statistical information storage unit as the aggregated destination statistical information. The communication apparatus according to Supplementary Note 2.

  (Supplementary Note 18) Communication means capable of outputting the aggregate destination management information stored in the aggregate destination management information storage means and the aggregate destination statistical information stored in the aggregate destination statistical information storage means The communication device according to appendix 17, characterized by:

(Additional remark 19) It has the aggregation destination statistics information storage means which memorize | stores the aggregation destination statistics information which is an aggregation result of the number of said frames output from each said physical link,
The allocating unit includes a statistical information writing unit that totalizes the number of frames output from each physical link and writes a totaling result to the aggregate destination statistical information storage unit as the aggregate destination statistical information. The communication apparatus according to appendix 1.

(Supplementary Note 20) In a communication apparatus that transfers a frame using a logical link configured by aggregating a plurality of physical links,
An input means for inputting a frame;
Aggregate destination management information storage means for storing aggregate destination management information indicating the physical link from which the frame is output;
Referring to the aggregated destination management information, the physical link from which the frame input by the input unit is output is determined to be one of the physical links that constitute the logical link. Minute means,
A plurality of output means composed of different physical links of the physical links constituting the logical link;
Have
The aggregate destination management information includes physical link information that identifies the physical link of each of the output means,
The allocating means sets the physical link that outputs the frame to the physical link that constitutes one of the output means, and sets the physical link that outputs the frame in response to a switching instruction to the other physical link. A communication apparatus characterized by switching to the physical link constituting the output means.

(Supplementary Note 21) One of the plurality of output means is an operation output means for outputting the frame, and the output means other than the operation output means are in a standby state in a state where the frame can be output. Standby output means
Aggregation management information storage means for storing aggregation management information indicating which of the plurality of output means is set as the operation output means,
The distribution means includes
Setting the output means set as the operation output means as the standby output means and setting at least one of the output means set as the standby output means as the operation output means In response to the switching instruction to switch the operation output means, the aggregate management information stored in the aggregation management information storage means is the standby output means instead of the output means that was the operation output means. A switching determination means for rewriting the output means that is the target of the switching instruction to a new setting for the operation output means;
The physical link that outputs the frame in advance is set as the physical link that constitutes the output means set in the operation output means, and the aggregate management information stored in the aggregate management information storage means Referring to, a distribution destination determination unit that switches the physical link that outputs the frame to the physical link that constitutes the standby output unit;
The communication apparatus according to appendix 20, wherein the communication apparatus includes:

(Supplementary Note 22) One of the plurality of output means is a standby output means that waits in a state where the frame can be output, and the output means other than the operation output means outputs the frame. Operational output means to
Aggregation management information storage means for storing aggregation management information indicating which of the plurality of output means is set as the operation output means,
The distribution means includes
At least one of the output means set as the operation output means is set as the standby output means, and the output means set as the standby output means is set as the operation output means Thus, in response to the switching instruction for switching the operation output means, the aggregation management information stored in the aggregation management information storage means is transferred to the output means that is the operation output means that is the target of the switching instruction. A switching determination unit that rewrites the output unit that is the standby output unit to a new one that is set in the operation output unit;
The physical link that outputs the frame in advance is set as the physical link that constitutes the output means set in the operation output means, and the aggregate management information stored in the aggregate management information storage means Referring to, a distribution destination determination unit that switches the physical link that outputs the frame to the physical link that constitutes the standby output unit;
The communication apparatus according to appendix 20, wherein the communication apparatus includes:

(Supplementary Note 23) In a communication apparatus that transfers a frame using a logical link configured by aggregating a plurality of physical links,
An input means for inputting a frame;
Aggregate destination management information storage means for storing aggregate destination management information indicating the physical link from which the frame is output;
Referring to the aggregated destination management information, the physical link from which the frame input by the input unit is output is determined to be one of the physical links that constitute the logical link. Minute means,
Aggregated destination statistical information storage means for storing aggregated destination statistical information which is a totaled result of the number of frames output from each of the physical links;
Have
The aggregated destination management information includes physical link information that identifies the physical link of each of a plurality of output units configured from a part of the physical links that are different from each of the physical links that configure the logical link,
The distribution means includes
Statistical information writing means for writing the aggregated result of the number of frames output from each physical link to the aggregated destination statistical information storage unit as the aggregated destination statistical information based on the result of determination by the allocating unit ,
The physical link that outputs the frame is set as the physical link that constitutes one of the output means, and the physical link that outputs the frame is configured as another output means in response to a switching instruction. A communication device that switches to the physical link.

(Supplementary Note 24) In a communication apparatus that transfers a frame using a logical link configured by aggregating a plurality of physical links,
An input means for inputting a frame;
Multicast destination management information storage means for storing multicast destination management information indicating the physical link to which the frame is output among the physical links that constitute the logical link and the physical links that do not constitute the logical link;
The physical link that constitutes the logical link and the logical link are not configured as the physical link that outputs the physical link from which the frame input by the input unit is output with reference to the multicast destination management information Multicast distribution means for determining the physical link that outputs the frame among the physical links;
A communication apparatus comprising:

(Supplementary Note 25) Redundant output means composed of the physical links constituting the logical link;
Independent output means configured from non-redundant physical links that are the physical links that do not constitute the logical links;
Have
The redundant system output means includes a working physical link that is the physical link that outputs the frame, and a backup physical link that is the physical link that waits in a state where the frame can be output.
Aggregate multicast destination management information storage means for storing aggregate multicast destination management information;
Aggregated multicast management storing aggregated multicast management information indicating which physical link is output from the physical link constituting the redundant output means and the physical link constituting the independent output means Information storage means;
Have
The multicast destination management information includes a plurality of working physical link information indicating a pattern comprising the working physical link of the redundant output means and the non-redundant physical link of the independent output means as the physical link for outputting the frame. And a plurality of spare physics, each of which indicates a pattern of a combination of the spare physical link of the redundant output means and the non-redundant physical link of the independent output means as the physical links that output the frame Link information,
The multicast distribution means includes hash calculation means for calculating a hash value using a hash function for frame part information constituting a part of the frame, multicast destination determination means, and multicast distribution destination determination means. And
The aggregated multicast destination management information is associated with each hash value calculated by the hash calculation means and each pattern indicated by the working physical link information, and each calculated by the hash calculation means The hash value is associated with each pattern indicated by the backup physical link information,
The multicast destination determining means includes
Whether to select the pattern indicated by the working physical link information with reference to the aggregated multicast information stored in the aggregated multicast management information storage means, or to select the pattern indicated by the backup physical link information Make a switching decision that is a decision,
With reference to the aggregated multicast destination management information stored in the aggregated multicast destination management information storage means, based on the result of the switching determination, the pattern of the working physical link information or the backup physical link information, Based on the hash value obtained by the calculation by the hash calculation means, the pattern of the physical link from which the frame is output is determined,
In the multicast destination management information, the pattern determined by the multicast destination determination means is associated with each physical link,
The multicast distribution destination determination unit refers to the multicast destination management information stored in the multicast destination management information storage unit, and based on the hash value obtained by the hash calculation unit calculating, 25. The communication apparatus according to appendix 24, wherein the physical link to which the frame is output is determined.

(Supplementary note 26) The aggregated multicast management information includes frame part specifying information for specifying the frame part information,
The multicast distribution means extracts the frame part information from the entire frame based on the frame part specifying information, and uses the extracted frame part information to cause the hash calculation means to perform the hash calculation. The communication apparatus according to appendix 25, further comprising a switching determination unit.

(Additional remark 27) The said aggregation multicast management information has the calculation content information which shows the calculation content of the said hash calculation,
26. The communication apparatus according to appendix 25, wherein the multicast distribution unit includes a multicast switching determination unit that causes the hash calculation unit to perform the hash calculation based on the calculation content information.

(Supplementary Note 28) The aggregated multicast management information includes operation non-execution information indicating that the hash calculation is not performed.
The multicast distribution means includes multicast switching determination means for determining the physical link that outputs the frame without performing the hash calculation when the calculation non-execution information is detected. The communication device described.

(Supplementary note 29) Flow destination management information storage means for storing flow destination management information indicating the transmission destination of the frame and indicating whether the frame is output by unicast or multicast;
Distributing means having flow destination determining means for deciding whether to output the frame by unicast or multicast by referring to the flow destination management information stored in the flow destination management information storage means When,
25. The communication device according to appendix 24, comprising:

(Additional remark 30) In the communication system which transfers a flame | frame using the logical link comprised by consolidating several physical links,
An input means for inputting a frame;
Aggregate destination management information storage means for storing aggregate destination management information indicating the physical link from which the frame is output;
Referring to the aggregated destination management information, the physical link from which the frame input by the input unit is output is determined to be one of the physical links that constitute the logical link. Minute means,
First output means comprising a part of the physical links of the physical links constituting the logical link;
Second output means comprising a part or all of the physical links of the physical links other than the physical links constituting the first output means of the physical links constituting the logical link. When,
Have
The aggregated destination management information includes first physical link information that identifies the physical link of the first output unit, and second physical link information that identifies the physical link of the second output unit. And
The distribution means includes
A first state in which the physical link from which the frame is output with reference to the first physical link information is determined as the physical link constituting the first output means, and the second physical link information The physical link from which the frame is output can be switched to a second state in which the physical link constituting the second output means is determined, and
A first communication device that switches from the first state to the second state in response to a switching instruction;
A communication system comprising: a second communication device connected to the first communication device by the physical link and to which the frame output from the first communication device is input through the logical link.

(Supplementary Note 31) A terminal device that is communicably connected to the first communication device and that can display information obtained by communicating with the first communication device.
The first communication device has communication means capable of communicating with the terminal device,
The terminal device
The aggregated destination management information and the aggregated destination statistical information are acquired by communication via the communication unit,
32. The communication system according to supplementary note 30, comprising display means capable of displaying the acquired aggregated destination management information and the aggregated destination statistical information.

(Supplementary Note 32) In a communication method for transferring a frame using a logical link configured by aggregating a plurality of physical links,
An input step in which the frame is input by an input means;
The distribution means is stored in the aggregate destination management information storage means, and the frame input by the input means is output with reference to the aggregate destination management information indicating the physical link from which the frame is output. Allocating the physical link to be one of the physical links constituting the logical link; and
A first output unit configured from a part of the physical links of the physical links configuring the logical link, or the first output unit of the physical links configuring the logical link is configured. An output step in which a second output means configured of a part or all of the physical links other than the physical link outputs the frame;
Have
The aggregated destination management information includes first physical link information that identifies the physical link of the first output unit, and second physical link information that identifies the physical link of the second output unit. And
In the allocating step, the allocating unit refers to the first physical link information, and determines the physical link from which the frame is output as the physical link constituting the first output unit. It is possible to switch between the first state and the second state in which the physical link from which the frame is output with reference to the second physical link information is determined as the physical link constituting the second output means And performing switching to switch from the first state to the second state in response to a switching instruction,
In the output step, the first output means outputs the frame from the physical link constituting the first output means based on the switching by the distribution means, or the second output means. Outputs the frame from the physical link constituting the second output means.

DESCRIPTION OF SYMBOLS 1 Communication apparatus 11 Input means 12 Aggregation destination management information storage means 12a Aggregation destination management table 13 Distribution means 14 1st output means 15 2nd output means

Claims (1)

In a communication device that transfers a frame using a logical link configured by aggregating a plurality of physical links,
An input means for inputting a frame;
Aggregated multicast destination management information in which identification information of a plurality of physical link patterns for outputting a frame is associated with each other when a working logical link is used and when a spare logical link is used instead of the working logical link First storage means for storing
Multicast destination management information indicating correspondence between the physical link from which the frame is output and the pattern identification information among the physical link constituting the logical link and the physical link not constituting the logical link is stored . Two storage means;
Depending on whether or not the current logical link can be used for the input frame, identification information of any pattern is acquired from the aggregated multicast destination management information , and the previous multicast destination management information is referred to serial among the physical links that do not constitute the physical link and the logical link constituting the logical link, the physical link corresponding to the acquired identification information of the pattern, vibration multicast determined as the physical link for outputting the frame Minute means,
A communication apparatus comprising:

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