JP2004120642A - Router apparatus and transfer control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a router apparatus which is operated at high speed and has high capacity by realizing a scalable router configuration in which it is considered as one router from the outside while performing efficient distributed processing. <P>SOLUTION: The side of each of a plurality of interface cards 3 is provided with an interface controller 5 for recording received data and judging whether the data are addressed to the present interface card or data to be transferred to the other interface card, and a CPU 4 for determining the interface card 3 to transfer the data by referring to a routing table for managing the transmission destination of the data when data judged to be transferred to the other interface card by the interface controller 5 are transferred, and transferring the data to the interface card 3 determined as the transfer destination. Thus, a load of the CPU for managing the entire router apparatus which is a problem for a conventional router apparatus is reduced. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a router device that realizes efficient distributed processing.
[0002]
[Prior art]
FIG. 17 shows the configuration of a conventional router. In FIG. 17, the router includes a CPU 101 and interface cards 103 to 105 connected to a bus 102. Although a router configuration having three interface cards is described here for ease of description, the number of interface cards may be arbitrary. Upon receiving a packet from the external network, the interface cards 103 to 105 transmit the packet to the CPU 101 using the bus 102. Upon receiving the packet, the CPU 101 starts a packet processing process, and searches for information necessary for transferring the packet, such as a NextHop or an output interface card, using the routing information created by a routing protocol or the like. The CPU 101 performs a packet rewriting process such as encapsulation based on a search result of the routing information and the layer 2 information, and transfers the packet to the interface cards 103 to 105 using the bus 102. The interface cards 103 to 105 that have received the packet from the CPU 101 perform queuing processing and the like if necessary, and output the packet to the network.
[0003]
Further, as patent documents that disclose a technique related to a router including a plurality of network interfaces, those described in Patent Documents 1 and 2 below are known.
[0004]
[Patent Document 1]
JP-A-7-202930
[Patent Document 2]
JP-A-6-97965
[0005]
Japanese Patent Application Laid-Open No. 7-202930 as Patent Document 1 discloses that in a MAC bridge composed of a plurality of network interfaces, access to a bus when referring to a table, memory contention, and performance degradation due to information exchange between CPUs are small. A MAC bridge table management method for performing simple and efficient table management is disclosed.
More specifically, as shown in FIG. 18, a MAC bridge () including one management CPU (202) and one or more network interfaces (203) having one or more ports (204). In 201), each network interface registers the source MAC address of the received frame in the local MAC address table and also registers the source MAC address of the frame transferred from the other network interface, thereby individually Manages a local MAC address table. Also, by transmitting the respective learning information to the master MAC address table (205) of the management CPU, the MAC address table information of the entire bridge is unified.
[0006]
Japanese Patent Application Laid-Open No. 6-97965 as Patent Document 2 discloses that a router having a plurality of network interfaces can speed up a routing process irrespective of the number of interfaces and communication traffic between networks. A relay control scheme has been proposed.
Specifically, as shown in FIG. 19, a plurality of network interfaces 320 in the router each have a filtering control unit 340 and a routing control unit 330, and the filtering control unit 340 is a terminal connected to its own network. The high-speed filtering of the communication in the network is performed by the filtering table 341 storing the address of the terminal, and the routing control unit 330 stores the address of the terminal and the interface number of the connected network interface as one set. By routing the communication between the networks by the table 331, the filtering processing capability and the routing processing can be performed independently of the number of network interfaces and the communication traffic between the networks. It is going to be able to improve the ability.
[0007]
[Problems to be solved by the invention]
In recent years, in order to cope with an ever-increasing amount of IP traffic, there is a great need for a router having a higher speed and a larger capacity. However, in order to realize high speed and large capacity with the conventional router configuration, it is basically necessary to enhance hardware such as high speed and large capacity of CPU, bus and interface card. However, achieving high speed and large capacity by strengthening the hardware is extremely costly, and when using general-purpose products, it can only achieve the same level of speed and large capacity as other companies. is there. Therefore, there is a case in which it is considered to change the router configuration to realize distributed processing by using a plurality of CPUs. However, while realizing distributed processing by using a plurality of CPUs, a router configuration that is externally viewed as one router is designed. That is extremely difficult.
[0008]
In addition, how to distribute the functions of the functions installed on multiple interface cards and the functions installed on the management device that manages them can be used to manage the router itself while achieving efficient distributed processing. No invention has been disclosed as to whether such labor can be reduced.
That is, the invention described in the technical document 1 mentions only a table management method, and describes how to efficiently transfer packets without causing access to the management CPU at the time of actual packet transfer. It is not described whether it will be realized.
Further, the invention described in Technical Document 2 does not disclose how to efficiently update the routing table provided in each network interface when the routing information is updated.
[0009]
Also, the inventions described in Patent Documents 1 and 2 described above include a plurality of network interfaces, each of which performs distributed processing, so that feedback occurs during packet transfer, causing a delay in packet transfer. It has the defect of.
[0010]
The present invention has been made in view of the above circumstances, and realizes a scalable router configuration that can be treated as one router from the outside while performing efficient distributed processing, thereby realizing high speed and large capacity router. It is an object to provide an apparatus and a transfer control method.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, an invention according to claim 1 is a router device having a plurality of interface cards and management control means for managing the plurality of interface cards, wherein the plurality of interface cards receive While recording the data, the interface control means determines whether the data is the data addressed to itself or the data to be transferred to another interface card, and transfers the data to another interface card by the interface control means. Upon receiving the transfer of the data determined to be the data to be transmitted, the interface card of the data transfer destination is determined with reference to the first management table for managing the destination of the data, and the interface card of the determined transfer destination is determined. Transfer control means for transferring data to the Interface control unit on the transmission side that has received the transfer of data from the transfer control unit, and outputs the data to the outside.
[0012]
According to a second aspect of the present invention, in the first aspect of the present invention, the management control unit, which receives the data determined to be the data addressed to itself from the interface control unit, determines whether the data is a routing protocol. In addition, the recording contents of the second management table for managing the transmission destination of the data are updated, and the routing information is transferred to the transfer control means in the plurality of interface cards to update the routing information.
[0013]
According to a third aspect of the present invention, in the first or second aspect of the present invention, the interface control means, when the layer 2 source address of the received data is an unlearned layer 2 source address, In addition to registering it in the held layer 2 address management table, the update information is notified to the transfer control means in the interface card and the interface control means in the other interface card, and the update of the layer 2 address management table in the router device is performed. It is characterized by performing.
[0014]
According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, it is determined to which interface card each VLAN (Virtual LAN) whose configuration range is limited to each interface card is connected. The first management table is recorded, and when the correspondence between the IP address and the layer 2 destination address is not recorded in the first management table, the transfer control unit determines that the data is to be transferred. An interface card including the set VLAN is detected by referring to the first management table, and data is transferred to the interface card.
[0015]
According to a fifth aspect of the present invention, in the first aspect of the present invention, the data transfer between the plurality of interface cards and the management control means is performed by a crossbar switch arranged on a bus. It is characterized by being.
[0016]
The invention according to claim 6 is a transfer control method in a router device having a plurality of interface cards and management control means for managing the plurality of interface cards, wherein the data received by the interface card on the receiving side is received. And a first determining step of determining whether the data is data addressed to itself or data to be transferred to another interface card, and a first determining step of managing a data transmission destination. With reference to the management table, a destination of the data determined to be data to be transferred to another interface card in the first determination step is determined, and the data is transferred to the determined destination interface card. And an interface card on the transmission side, the And outputting the transferred data from Sukado on the network.
[0017]
According to a seventh aspect of the present invention, in the sixth aspect of the invention, the data determined to be the data addressed to itself in the first determination step is transferred to the management control means, and the data is a routing protocol. And if the data is a routing protocol, update the recorded contents of the second management table managed by the management control means in which the data transmission destination is registered, and And a routing information update step of updating the routing information by transferring the information to a third party.
[0018]
The invention according to claim 8 is the interface card according to claim 6 or 7, wherein the interface card determines whether the layer 2 source address of the received data is an unlearned layer 2 source address. 2 and, if the source address is an unlearned layer 2 source address, register it in the layer 2 address management table managed by the interface card, and notify other interface cards of the update information, And a notifying step of updating the layer 2 address management table.
[0019]
According to a ninth aspect of the present invention, in the invention according to any one of the sixth to eighth aspects, which VLAN (Virtual LAN) whose configuration range is limited to each interface card is connected to which interface card. The data is recorded in the first management table, and when the interface card on the receiving side receives a transfer of data for which the correspondence between the IP address and the layer 2 destination address is not recorded in the first management table, the transfer of the data is performed. The method includes a second transfer step of detecting an interface card including a VLAN set as a destination by referring to the first management table, and transferring data to the interface card on the transmission side.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of the router device and the transfer control method of the present invention will be described in detail with reference to the accompanying drawings. 1 to 16 show an embodiment of a router device and a transfer control method according to the present invention.
[0021]
[First Embodiment]
First, the configuration of the present embodiment will be described with reference to FIG. In the present embodiment, as shown in FIG. 1, a CPU 1 and a plurality of interface cards 3 (in FIG. 1, three interface cards 3-1, 3-2, 3- 3 is connected to the bus 2, but the number of interface cards may be arbitrary as shown in FIG. 2). The interface cards 3-1, 3-2, and 3-3 are interface controllers 5-1 and 5-2 that realize input and output of packets with the CPUs 4-1, 4-2 and 4-3 for realizing distributed processing. , 5-3. Here, for ease of explanation, a configuration in which one CPU 4 and one interface controller 5 are mounted on the interface card 3 will be described, however, the number of CPUs 4 and interface controllers 5 may be arbitrary, and FIG. The CPU 4 can be shared by a plurality of interface cards 3 as shown in FIG.
[0022]
The CPU 1 that manages the entire router can communicate with the CPUs 4-1, 4-2, 4-3 and the interface controllers 5-1, 5-2, 5-3 via the bus 2. Further, the CPU 1 has a database in which routing information is registered.
[0023]
The bus 2 connects each part of the router so that the CPUs 1, 4-1, 4-2, and 4-3 and the interface controllers 5-1, 5-2, and 5-3 can communicate with each other. In addition, dedicated hardware such as a crossbar switch is arranged on the bus 2 to realize packet transfer. By using dedicated hardware such as a crossbar switch, an inexpensive and high-speed internal connection can be realized. Here, the bus is represented as a single bus to represent the function of connecting the inside of the device, but it is actually possible to configure the bus for packet transfer and communication between CPUs.
[0024]
The CPU 4 that performs packet transfer is connected to the bus 2 and the interface controller 5 (CPU 4-1 and interface controller 5-1, CPU 4-2 and interface controller 5-2, CPU 4-3 and interface controller 5-3). , The CPU 1, the other CPU 4, and the interface controllers 5-1, 5-2, 5-3. Each of the CPUs 4-1, 4-2, and 4-3 in the plurality of interface cards stores routing information, an address used in layer 2 (hereinafter, referred to as layer 2 information), and a correspondence relationship between an IP address and layer 2 information. And a management table for managing the information indicating the information.
[0025]
The interface controller 5 is connected to the bus 2 and the CPU 4 (the interface controller 5-1 and the CPU 4-1, the interface controller 5-2 and the CPU 4-2, the interface controller 5-3 and the CPU 4-3), and receives data from outside. The transferred packet is transferred to the CPUs 1-1, 4-1, 4-2, 4-3 or another interface controller 5. Further, it has a function of performing processing such as queuing on packets received from the CPUs 1-1, 4-1, 4-2, and 4-3 and other interface controllers 5, and outputting the packets to the outside. Each of the interface controllers 5-1, 5-2, and 5-3 has a layer 2 table for managing layer 2 information. The layer 2 table is a table in which data used when transferring (forwarding) a layer 2 frame is recorded, and is used to determine an output destination port and a frame format from a MAC address and VLAN (Virtual LAN) information. used.
[0026]
The present embodiment having the above configuration realizes efficient distributed processing by optimally performing the function allocation between the functions mounted on the plurality of interface cards and the functions mounted on the management device that manages them. It is another object of the present invention to realize a router device in which the time required for managing the router itself is reduced.
[0027]
Therefore, the present embodiment records the received data on the plurality of interface cards 3 and determines whether the data is data addressed to itself or data to be transferred to another interface card. When the interface controller 5 receives the transfer of the data determined to be the data to be transferred to another interface card by the interface controller 5, the transfer is performed by referring to the routing information of the management table for managing the destination of the data. And a CPU 4 for determining the destination interface card 3 and transferring data to the determined destination interface card 3.
[0028]
In addition, the CPU 1 that manages the entire router device determines whether or not the packet determined to be the protocol packet by the interface controller 5 is a routing protocol. In addition to the updating, a function of transferring the routing information to the CPUs 4 in the plurality of interface cards 3 and updating the routing information in the management table is provided. Note that the protocol packet refers to a packet such as an application protocol such as TELNET and FTP (File Transfer Protocol) addressed to the own router, a routing protocol such as OSPF (Open Shortest Path First Routing) and RIP (Routing Information Protocol), and the like. The destination address and the IP address are packets addressed to the own router.
[0029]
With the router device having such a configuration, at the time of packet transfer, the CPU 4 on the input side selects the interface controller 5 as the output destination of the data, and transfers the data to the selected interface controller 5 to perform layer 2 transmission. By performing processing such as processing and outputting to the outside, packet transfer is realized only by the interface controller 5 and the CPU 4 provided in the interface card 3, and the entire router device which has been a problem in the conventional router device is managed. The load on the CPU 1 can be reduced.
[0030]
Also, only when the received data is a protocol packet, the data is transmitted to the CPU 1 that manages the whole, and when the data is the routing protocol, the recorded contents of the database are updated, By transferring the routing information to the CPU 4 and updating the routing information in the management table, it becomes possible to treat a router device having a plurality of CPUs as equivalent to a conventional router device having a single CPU. It is possible to reduce the trouble of managing the router device at the time of setting of the router.
[0031]
Next, more detailed operations of the components of the router device will be described.
First, the operation procedure of the interface controller 5 will be described with reference to FIGS.
The interface card 3 that has received the data transferred from the outside (step S401 / YES) stores the received data in the interface controller 5 (step S402). Next, the layer 2 destination address and the source address of the received data are confirmed (step S403).
[0032]
If the source address is an unlearned address (there is a source address that needs to change the layer 2 information) (step S404 / YES), the source address is registered in the layer 2 table held by the interface controller 5. (Step S405). Further, the interface controller 5 notifies the learned layer 2 information to the CPU 4 and the other interface controllers 5 in the own card via the bus 2 (step S406). Further, the layer 2 information notified in this case is only the changed layer 2 information.
[0033]
If the layer 2 destination address of the received data is the address of the router itself (step S407 / YES), the interface controller 5 determines whether the packet is a protocol packet (step S409). For example, a filter can be used as the determination method.
[0034]
If the packet is a protocol packet (step S409 / YES), the packet is transferred to the CPU 1 (step S410). The CPU 1 that has received the protocol packet processes the packet in accordance with the procedure defined by the protocol, similarly to the CPU mounted on the conventional router. In particular, if the protocol packet is a routing protocol, the database storing the routing information is changed as necessary, and the changed routing information is distributed to other interface cards.
[0035]
If the packet is not a protocol packet (step S409 / NO), the packet is transferred to the CPU 4 in the own card (step S411). The CPU 4 receiving the packet determines the output destination interface controller using the routing information and the layer 2 information held in the management table, and transfers the packet subjected to the processing such as encapsulation to the interface controller.
[0036]
Next, a process when data is received from another interface card 3 will be described with reference to FIG.
When receiving data transfer from another interface card 3 (step S501), the interface controller 5 determines whether the data is a transfer packet (step S502). If the data is a transfer packet (step S502 / YES), the packet is subjected to processing such as layer 2 processing and queuing (step S503), and output to the outside (step S504). If the data is the layer 2 information (step S505 / YES), the notified address information is registered in the layer 2 information held in the layer 2 table (step S506), and the The information is notified (step S507).
[0037]
Next, the overall operation of the present embodiment will be described by dividing it into three processes: protocol processing of layer 3 or higher, learning processing of a layer 2 address, and packet transfer processing. First, the protocol processing of the layer 3 or higher will be described with reference to FIG. Here, for ease of explanation, it is assumed that the interface card 3-1 has received the protocol packet, but the interface card that receives the protocol packet is not limited to 3-1.
[0038]
The interface card 3-1 ((1) shown in FIG. 6) that receives a protocol packet such as a routing protocol from the outside stores the packet in the interface controller 5-1. Next, the interface controller 5-1 checks the layer 2 destination address of the received packet ((2) shown in FIG. 6). When the layer 2 destination address is its own address (router address), it is determined whether the packet is a protocol packet ((3) shown in FIG. 6). The packet can be determined using, for example, a filter. The interface controller 5-1 that determines that the stored packet is a protocol packet transfers the packet to the CPU 1 using the bus 2 ((4) shown in FIG. 6). The CPU 1 that has received the protocol packet processes the packet in accordance with the procedure defined by the protocol, similarly to the CPU mounted on the conventional router. In particular, when the protocol packet is a routing protocol, the database storing the routing information is updated as needed.
[0039]
Here, a process when the routing information is updated will be described with reference to FIG. The CPU 1 that has updated the routing information distributes the routing information to the CPUs 4-1, 4-2, and 4-3 with the update as a trigger. In a large-scale network, routing information to be distributed may be large. Depending on the configuration of the bus 2, the bus may be occupied while large-scale routing information is being distributed. In such a case, a method of dividing and distributing the routing information is used. Shall be.
[0040]
Returning to FIG. 6, the protocol processing will be described continuously. When a response is required for the received protocol packet, the CPU 1 creates a response packet on the CPU 1 ((5) shown in FIG. 6) and transmits the packet to the interface controller 5-1 using the bus 2. ((6) shown in FIG. 6). After receiving the packet, the interface controller 5-1 performs necessary processing such as queuing and outputs the packet to the outside ([7] shown in FIG. 6).
[0041]
Next, a learning process of the layer 2 address will be described with reference to FIG. In the following, for the sake of simplicity, it is assumed that the interface card 3-1 has received the frame, but the interface card that receives the frame is not limited to 3-1.
[0042]
The interface card 3-1 that has received the layer 2 frame stores the frame in the interface controller 5-1 ((1) shown in FIG. 8). At this time, the interface controller 5-1 checks the source address of the frame ([2] shown in FIG. 8). If the source address is an unlearned source address, the interface controller 5-1 holds the layer 2 Register it in the table ((3) shown in FIG. 8). Further, the interface controller 5-1 notifies the CPU 4-1 in the own card 3 and the other interface controllers 5-2 and 5-3 of the learned layer 2 information using the bus 2 (see FIG. 8). (4). After receiving the layer 2 information, the interface controllers 5-2 and 5-3 register the notified layer 2 information in the layer 2 table ((5) shown in FIG. 8), and thereafter, the CPUs 4-2 and 4-3. Is notified of the layer 2 information ([6] shown in FIG. 8).
[0043]
Next, the packet transfer process will be described with reference to FIG. In the following, for ease of explanation, it is assumed that the interface card 3-1 has received the protocol packet. However, the interface card that receives the packet is not limited to 3-1.
[0044]
The interface card 3-1 that has received the packet stores the packet in the interface controller 5-1 ((1) shown in FIG. 9). After confirming that the layer 2 destination address is the router address, the interface controller 5-1 determines whether the packet is to be transferred to another interface controller 5-2 or 5-3 or a protocol packet to be transferred to the CPU 1. ((2) shown in FIG. 9). This determination method can be performed using, for example, a filter. The interface controller 5-1 that determines that the stored packet is a packet to be transferred to another interface controller 5, transfers the packet to the CPU 4-1 ((3) shown in FIG. 9). The CPU 4-1 having received the packet from the interface controller 5-1 determines the output destination interface controller using the routing information and the layer 2 information held in the management table. In this operation example, it is assumed that the output destination interface card is 3-2 for convenience of explanation. After performing processing such as encapsulation on the packet ((4) shown in FIG. 9), the CPU 4-1 transfers the packet to the interface controller 5-2 ((5) shown in FIG. 9). After receiving the packet, the interface controller 5-2 performs processing such as layer 2 processing and queuing necessary for output ((6) shown in FIG. 9), and then outputs the packet (shown in FIG. 9). (7)). In the above description, the transfer processing is performed by the CPU. However, the transfer processing can be performed only by hardware without passing through the CPU by notifying the interface controller of the information held by the CPU.
[0045]
As described above, the present embodiment can realize a scalable router configuration that can be treated as one router by the user while performing efficient distributed processing, and can achieve high-speed and large-capacity routers.
[0046]
[Second embodiment]
Next, a second embodiment according to the present invention will be described with reference to the accompanying drawings. In the present embodiment, the configuration range of a VLAN (Virtual LAN) is limited in units of interface cards. The configuration of this embodiment is shown in FIG. 1 as in the above-described first embodiment, but differs in the operation. The operation of the present embodiment will be described with reference to FIG.
[0047]
As in the case of the first embodiment, the description will be made by dividing into protocol processing, layer 2 address learning processing, and packet transfer processing. However, since the protocol processing is the same as in the first embodiment, the description is omitted.
[0048]
Regarding the learning processing of the layer 2 address, since the configuration range of the VLAN is limited in units of the interface card, the layer 2 information is not notified to other interface cards. Therefore, it is possible to realize a device configuration that does not exchange layer 2 information.
[0049]
The operation procedure relating to the packet transfer will be described with reference to FIG. Here, for ease of explanation, it is assumed that the interface card 3-1 has received the protocol packet, but the interface card that receives the packet is not limited to 3-1.
[0050]
The interface card 3-1 that has received the packet stores the packet in the interface controller 5-1 ((1) shown in FIG. 10). The interface controller 5-1 that has confirmed that the layer 2 destination address is a router address determines whether the packet is to be transferred to another interface controller 5-2 or 5-3 or a protocol packet to be transferred to the CPU 1. ((2) shown in FIG. 10). This determination method can be performed using, for example, a filter. The interface controller 5-1 that has determined that the stored packet is a packet to be transferred to another interface controller transfers the packet to the CPU 4-1 ((3) shown in FIG. 10). The CPU 4-1 that has received the packet from the interface controller 5-1 determines the output destination interface controller using the routing information held in the management table ((4) shown in FIG. 10). In this operation example, it is assumed that the output destination interface card is 3-2 for convenience of explanation. The CPU 4-2 that has received the packet ((5) shown in FIG. 10) from the CPU 4-1 performs processing such as encapsulation of the packet ((6) shown in FIG. 10) using the layer 2 information. After the execution, the packet is transferred to the interface controller 5-2 ((7) shown in FIG. 10). The interface controller 5-2 performs processing such as layer 2 processing and queuing necessary for output ([8] shown in FIG. 10), and then outputs the packet ([9] shown in FIG. 10). .
[0051]
As described above, the packet transfer based on the distributed processing is realized without sharing the layer 2 information between the interface cards, and a router structure that operates as one router from the outside can be realized. It is to be noted that the transfer processing can be performed only by hardware without passing through the CPU by notifying the information held by the CPU to the interface controller, as in the above-described embodiment.
[0052]
Here, the packet transfer when the correspondence between the IP address and the layer 2 address is not cached is compared between the case where the configuration range of the VLAN is not limited to the interface card unit and the case where the VLAN configuration range is limited. 11 to 15 show the procedure of packet transfer. 11 to 15, input / output ports of each interface card are described in the interface card to facilitate the description of packet transfer. First, a case in which the configuration range of the VLAN is not limited to the interface card unit will be described.
The router receives a packet to be transferred to another interface controller (hereinafter, a transfer packet) from the port 1 of the interface card 3-1 ((1) shown in FIG. 11) and transfers the packet to the CPU 4-1. ((2) shown in FIG. 11).
[0053]
Upon receiving the packet, the CPU 4-1 searches the management table and detects the output destination of the packet from the layer 2 information and the routing information. Here, the output destination is, for example, the VLAN set as the third VLAN, and the third VLAN is assumed to be accommodated in both of the interface cards 3-2 and 3-3. That is, although the CPU 4-1 can detect the IP address of the NextHop router from the layer 2 information and the routing information, it is determined which port of the interface card 3-2 or 3-3 is connected to the router. I do not know.
[0054]
The CPU 4-1 requests the CPU 4-2, 4-3 for an ARP (Address Resolution Protocol) to detect which interface card the NextHop router is connected to and the Layer 2 address (see FIG. 11). (3) shown). Upon receiving the request, the CPUs 4-2 and 4-3 output an ARP request packet to each port connected to the interface card, and wait for an ARP response packet to return from the NextHop router (▲ shown in FIG. 11). 4 ▼). Here, it is assumed that a response packet is returned from the port 3 of the interface card 3-3. The interface controller 5-3 returns the received ARP response packet to the CPU 4-3 ((5) shown in FIG. 12). Further, the CPU 4-3 notifies the CPU 4-1 that the ARP response packet has been received ([6] shown in FIG. 12). The CPU 4-1 having received the notification of the reception of the ARP response packet transfers the packet to the CPU 4-3 ((7) shown in FIG. 13), and the packet is output to the port 3 of the interface card by the interface controller 5-3 (FIG. 13). (8) shown in FIG. 13).
[0055]
When a packet is transmitted to an unlearned destination in this way, feedback occurs from the interface card on the output side to the interface card on the input side. That is, the CPU 4-1 on the input side must keep holding the packet from receiving the packet until receiving the notification of the reception of the ARP response packet, which has a disadvantage that it takes time to transfer the packet. Upon receiving the ARP response packet, the CPU 4-3 determines that the learned contents (other than that the corresponding IP address is connected to the interface card 3-3 and has the layer 2 address described in the ARP response). Notify CPUs, that is, all CPUs have the same ARP table.
[0056]
Next, packet transfer in the case where the configuration range of the VLAN is limited in units of interface cards will be described.
The operation is the same as that described above until the CPU 4-1 which has received the packet transfer searches the management table and detects the packet output destination from the routing information and the layer 2 information. Here, since there is a restriction that one VLAN is stored in only one interface card, the VLAN to which a packet is output is not stored in a plurality of interface cards. Further, the routing information registered in the management table describes which VLAN is stored in which interface card.
[0057]
The CPU 4-1 uses ARP to detect which interface card the NextHop router is connected to and the layer 2 address thereof, but limits the configuration range of the VLAN to each interface card. Therefore, the packet can be transferred to the output destination VLAN before receiving the notification of the reception of the ARP response packet ((3) shown in FIG. 14). In this case, it is assumed that the interface card 3-3 stores the VLAN to be output. Upon receiving the packet, the CPU 4-3 refers to the management table to search whether or not the correspondence between the IP address and the layer 2 address is cached. If it is determined that there is no entry, the CPU 4-3 transfers the packet to the NextHop router. Output an ARP request packet to each port ((4) shown in FIG. 14). Here, it is assumed that an ARP response packet has been received from the port 3 connected to the interface card 3-3. Upon receiving the ARP response packet, the interface controller 5-3 returns the received packet to the CPU 4-3 ((5) shown in FIG. 15). Upon receiving the ARP response packet, the CPU 4-3 outputs the packet to the detected port via the interface controller 5-3 to transfer the packet to the NextHop router ((6) shown in FIG. 16). ).
[0058]
By limiting the configuration range of the VLAN on a per interface card basis, no feedback occurs from the output side CPU to the input side CPU, and it is possible to transfer packets at a higher speed.
[0059]
The above-described embodiment is a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.
[0060]
【The invention's effect】
As is apparent from the above description, the present invention records received data on a plurality of interface cards and determines whether the data is data addressed to itself or data to be transferred to another interface card. An interface control unit for determining whether there is a data, and a first management table for managing a transmission destination of the data when receiving the transfer of the data determined to be the data to be transferred to another interface card by the interface control unit. Transfer control means for determining an interface card to which data is to be transferred by referring to the interface card, and transferring the data to the determined interface card to which the data is to be transferred.
[0061]
The management control means for managing the entire router device determines whether or not the packet determined to be a protocol packet by the interface control means is a routing protocol. In addition to updating the contents, a function is provided for transferring routing information to transfer control means in a plurality of interface cards to update the routing information.
[0062]
By using the router device having such a configuration, when transferring a packet, the transfer control unit on the input side selects the interface control unit as the output destination of the data, and transfers the data to the selected interface control unit. By outputting the packet to the outside, the packet transfer is realized only by the interface control means and the transfer control means provided in the interface card, and the load on the CPU for managing the entire router device, which has been a problem in the conventional router device, is reduced. Can be reduced.
[0063]
In addition, when the received data is a protocol packet, the data is transmitted to the management control unit that manages the entire data. By transferring the routing information of the transfer control means and updating the routing table, it becomes possible to treat a router device having a plurality of CPUs in the same manner as a conventional router device having a single CPU. In such a case, the trouble of managing the router device can be reduced.
[0064]
Further, when receiving a transfer of data in which the correspondence between the IP address and the layer 2 destination address is not recorded in the first management table, the interface card including the VLAN set as the transfer destination of the data is transferred to the first card. By detecting the data by referring to the management table and transferring the data to the interface card, the transfer control means on the input side does not know the interface card as the data output destination, and inquires the other interface card of the data output destination. Such a feedback operation can be prevented, and data transfer can be realized with a minimum delay.
[0065]
Further, data transfer between the plurality of interface cards and the management control means is performed by a crossbar switch arranged on the bus, so that a plurality of CPUs can be connected by inexpensive and high-speed internal connection.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a first embodiment according to the present invention.
FIG. 2 is a diagram illustrating another configuration of the router device.
FIG. 3 is a diagram showing another configuration of the router device.
FIG. 4 is a flowchart showing an operation procedure of the interface controller 5;
FIG. 5 is a flowchart showing an operation procedure of the interface controller 5;
FIG. 6 is a diagram showing an operation procedure of the router device.
FIG. 7 is a diagram showing an operation procedure of the router device.
FIG. 8 is a diagram showing an operation procedure of the router device.
FIG. 9 is a diagram showing an operation procedure of the router device.
FIG. 10 is a diagram showing an operation procedure of the router device.
FIG. 11 is a diagram showing an operation procedure of the router device.
FIG. 12 is a diagram showing an operation procedure of the router device.
FIG. 13 is a diagram showing an operation procedure of the router device.
FIG. 14 is a diagram illustrating an operation procedure of the router device.
FIG. 15 is a diagram illustrating an operation procedure of the router device.
FIG. 16 is a diagram showing an operation procedure of the router device.
FIG. 17 is a block diagram showing a configuration of a conventional router device.
FIG. 18 is a block diagram showing a configuration of a conventional router device.
FIG. 19 is a block diagram showing a configuration of a conventional router device.
[Explanation of symbols]
1 CPU
2 bus
3-1、3-2、3-3 Interface card
4-1、4-2、4-3 CPU
5-1, 5-2, 5-3 Interface controller

Claims (9)

A router device having a plurality of interface cards and management control means for managing the plurality of interface cards,
The plurality of interface cards,
Interface control means for recording the received data and determining whether the data is data addressed to itself or data to be transferred to another interface card;
Upon receiving the transfer of the data determined to be the data to be transferred to another interface card by the interface control means, referring to the first management table for managing the data transmission destination, the interface of the data transmission destination Transfer control means for determining a card and transferring the data to the determined transfer destination interface card;
Has,
The router device, wherein the transmission-side interface control unit that has received the data transfer from the reception-side transfer control unit outputs the data to the outside. The management control unit, which has received the data determined to be the data addressed to itself from the interface control unit, manages a data transmission destination when the data is a routing protocol. 2. The router device according to claim 1, wherein the contents of the table are updated, and the routing information is transferred to the transfer control means in the plurality of interface cards to update the routing information. When the Layer 2 source address of the received data is an unlearned Layer 2 source address, the interface control unit registers the Layer 2 address in the Layer 2 address management table held by the interface control unit and transfers the data in the interface card. 3. The router according to claim 1, wherein the update information is notified to the control means and the interface control means in another interface card, and the layer 2 address management table in the router is updated. The first management table records which interface card is connected to each VLAN (Virtual LAN) whose configuration range is limited to each interface card,
An interface including a VLAN set as a transfer destination of the data, when the transfer control unit receives the transfer of the data in which the correspondence between the IP address and the layer 2 destination address is not recorded in the first management table; 4. The router device according to claim 1, wherein a card is detected by referring to the first management table, and the data is transferred to the interface card. 5. The router device according to any one of claims 1 to 4, wherein data transfer between the plurality of interface cards and the management control unit is performed by a crossbar switch arranged on a bus. A transfer control method in a router device having a plurality of interface cards and management control means for managing the plurality of interface cards,
In the interface card on the receiving side,
A first determination step of recording the received data and determining whether the data is data addressed to itself or data to be transferred to another interface card;
With reference to a first management table for managing data transmission destinations, a destination of data determined to be data to be transferred to another interface card in the first determination step is determined, and the determined destination is determined. A first transfer step of transferring the data to a transfer destination interface card,
A transfer control method comprising: outputting, on a network, data transferred from an interface card on a receiving side to an interface card on a transmitting side. The data determined to be the data addressed to itself by the first determination step is transferred to the management control unit, and it is determined whether the data is a routing protocol. In the case where there is a routing, the destination of the data is registered, the recorded content of the second management table managed by the management control means is updated, and the routing information is transferred to the plurality of interface cards to update the routing information. 7. The transfer control method according to claim 6, further comprising an information updating step. In the interface card,
A second determining step of determining whether the layer 2 source address of the received data is an unlearned layer 2 source address;
If the address is an unlearned layer 2 source address, the address is registered in a layer 2 address management table managed by the interface card, and update information is notified to another interface card. Notification process for updating the
8. The transfer control method according to claim 6, wherein: The first management table records which interface card is connected to each VLAN (Virtual LAN) whose configuration range is limited in units of interface cards,
When the interface card on the receiving side receives a transfer of data for which the correspondence between the IP address and the layer 2 destination address is not recorded in the first management table, the interface card includes the VLAN set as the transfer destination of the data. 9. The method according to claim 6, further comprising a second transfer step of detecting an interface card with reference to the first management table and transferring the data to the interface card on the transmitting side. The transfer control method described in the section.

Images