JP2000032023A - Virtual lan system and network management method applied to the virtual lan system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the network management that solves a fault quickly. SOLUTION: In the case of transmitting a frame from a station 4 to a station 6 being a same virtual LAN group, a repeater 2 adds a virtual LAN identifier to specify a group of the network NA and a reception port to the frame because a sender network NA connects directly to a port, a repeater 3 sends the frame from which the virtual LAN identifier is eliminated to a network NC because a destination network NC directly connects to a port, and a network management device 1 specifies a group of the sender network and a reception port based on the virtual LAN identifier in the frame that is relayed between the repeaters 2, 3 to figure out a fault occurrence point.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a virtual LAN system in which a plurality of networks are connected by a relay device and virtually communicates using a virtual LAN identifier, and a network management method applied to the virtual LAN system.

[0002]

2. Description of the Related Art In recent network systems, with the diversification, complexity, and expansion of networks, it is general that a plurality of networks are connected by a large number of relay devices. In addition, the movement of servers and terminals frequently occurs on the network, and in order to cope with this, the introduction of a virtual LAN in which the physical connection and the logical connection are different has been advanced.

[0003] Here, a virtual LAN system will be described. FIG. 11 is a diagram illustrating a frame format used in a conventional virtual LAN system, and FIG. 12 is a configuration diagram illustrating an example of a conventional virtual LAN system. The frame for the virtual LAN shown in FIG. 11 includes a destination MAC address, a source MAC address, and a virtual LAN (in each figure, a V-LAN
), An identifier, a data length, data, and a frame check sequence (FCS). In particular, the virtual LAN identifier is virtual LAN group identification information formed by a bit string (N bits, N is a natural number) for identifying a virtual LAN group.

[0004] The virtual LAN system has a configuration in which a plurality of virtual LAN groups are connected by a plurality of relay devices (for example, switch hubs). An example is shown in FIG.
Is shown in That is, FIG. 12 shows a virtual LAN system in which a plurality of switch hubs 51 to 54 are connected to the switch hub 50. Switch hub 5
0 includes, for example, four ports # 1, # 2, # 3, and # 4, and connects the switch hubs 51, 52, 53, and 54 to the ports # 1, # 2, # 3, and # 4. I have. Also,
Each of the switch hubs 51 to 54 has seven ports, and the switch hub 50 is connected to each of the ports # 7.

[0005] In the above virtual LAN system, there are four virtual LAN groups as an example. The group names are A, B, C, D. In the switch hub 51, ports # 1, # 2, # 3, # 4, #
Nodes A1 (group A), B
1 (group B), C1 (group C), A2 (group A), D1 (group D), and A3 (group A). In the switch hub 52, the ports # 1, # 2, # 3, # 4, # 5, and # 6 respectively have nodes A4 (group A), B2 (group B), and C2.
(Group C), D2 (Group D), D3 (Group D), and C3 (Group C) are assigned.

In the switch hub 53, ports # 1, # 2, # 3, # 4, # 5, and # 6 are connected to nodes A5 (group A), B3 (group B), and C4, respectively.
(Group C), B4 (Group B), D4 (Group D), and A6 (Group A) are assigned. In the switch hub 54, the ports # 1, # 2, # 3, #
Nodes A7 (group A), B5 (group B), C5 (group C), B6
(Group B), D5 (Group D), and D6 (Group D) are assigned.

In the above virtual LAN system, communication is performed using frames having the format shown in FIG. At that time, a virtual LAN group is identified from the virtual LAN identifier, and transmission and reception are performed according to the source MAC address and the destination MAC address.

In FIG. 12, node B1
When a frame is transmitted to the switch hub 50 (the transmission path is indicated by a dashed line in FIG. 12), the frame is received at the port # 2 (node B1) of the switch hub 51. From port # 7 of switch hub 52 to port # 2 via ports # 1 and # 2
(Node B2). When frame transmission is performed from the node B6 to the node B2 (see FIG. 12).
The transmission path is indicated by a two-dot chain line), a frame is received at port # 4 (node B6) of the switch hub 54, and the received frame is transmitted to the ports # 4 and # of the switch hub 50.
2, and is transmitted from port # 7 of switch hub 52 to port # 2 (node B2).

[0009]

SUMMARY OF THE INVENTION The above-described virtual L
In the AN system, the node B1 and the node B6 sometimes use the same MAC address. in this way,
When a frame is transmitted from the node B2 to the node B1 in the presence of the duplicate MAC address, even if the MAC address is set to the node B1 on the node B2 side, the node B6 shares the MAC address. Therefore, the same frame is also received by the node B6.

As a result, the node B2 should receive a response only from the node B1, but also receives a response from the node B6, which may cause an abnormality in the processing in the node B2. This means that in the system, the frame has only a virtual LAN identifier for identifying the virtual LAN group, and there is no difference between the frame transmitted from the node B1 to the node B2 and the frame transmitted from the node B6 to the node B1. Due to that. As a result, under the present circumstances, it was difficult to determine which node caused the failure.

[0011] From the above, the conventional virtual LAN
It has to be noted that, in the system, since the logical configuration and the physical configuration of the network are different, even if a failure occurs in a certain place, it is extremely difficult to specify the place where the failure has occurred. Therefore, when a failure occurs, even if the frame that causes the failure is analyzed, the physical port to which the network device that causes the failure is connected is not known, and the location where the failure occurred cannot be specified, making it difficult to resolve the failure. There was a problem of becoming.

[0012] The present invention solves the above-mentioned problems of the prior art by providing a virtual LAN system and a network management method applied to the virtual LAN system for realizing network management capable of promptly finding a faulty network. The purpose is to provide.

[0013]

Means for Solving the Problems The above-mentioned problems are solved,
In order to achieve the object, a virtual LAN system according to the invention of claim 1 includes one or more relay devices connecting a plurality of networks, and network devices connected to the relay devices and connected to the plurality of networks. A network management device for logically grouping and managing the relationship, wherein the relay device is configured such that each of the source and destination is directly transmitted from a source network connected to a source network device among the plurality of networks. A virtual L that specifies a group to which the source network belongs and a port to which the source network is connected only when receiving a frame including a physical address.
A first frame processing means for adding AN identification information to the frame; and a first frame processing means for directly transmitting a frame to a network connected to a destination network device among the plurality of networks. Second frame processing means for removing virtual LAN identification information from the frame, wherein the network management device adds, to the virtual LAN identification information added by the addition means, of the frame relayed by the relay device. A group to which the source network belongs and a port to which the source network is connected are specified based on the group.

According to the first aspect of the present invention, in the relay device, only for a frame directly received from the source network, a virtual group for specifying a group to which the source network belongs and a port to which the source network is connected. LAN identification information is added, and virtual LAN identification information is removed from a frame directly transmitted to the destination network. In the network management device, the source of the frame relayed by the relay device is determined based on the virtual LAN identification information. Since the group to which the network belongs and the port to which the source network is connected are specified, it is possible to easily specify the network where the failure has occurred from the transmission frame relayed by the relay device. , A network for achieving fault resolution quickly It is possible to realize the management.

The virtual L according to the second aspect of the present invention.
The AN system according to claim 1, wherein the first frame processing means adds the virtual LAN identification information when no virtual LAN identification information is added to the received frame. .

According to the second aspect of the present invention, when the virtual LAN identification information is not added to the received frame, the virtual LAN identification information is added. Therefore, the virtual LAN identification information is added to the received frame. If no information is added, it is assumed that the port is directly connected to the network by a port, and that port information can be included in the virtual LAN identification information.

The virtual L according to the third aspect of the present invention.
The AN system according to claim 1 or 2, wherein the relay device stores a group corresponding to each port, and the first frame processing means corresponds to the port from the port at which the frame was received. The virtual LAN identification information including information for identifying a group and identifying the identified group is generated.

According to the third aspect of the present invention, when a frame including the physical addresses of the transmission source and the destination is directly received from the transmission source network connected to the transmission source network device, the frame is received. Since the port identifies the group corresponding to the port and generates the virtual LAN identification information including the information for specifying the group, the transmission frame is accurately associated with the group and the port. , It is possible to transmit the correspondence between an accurate group and its port to another relay device.

The virtual L according to claim 4 of the present invention.
The AN system according to claim 1 or 2, wherein the first frame processing means is indirectly connected to a transmission source network device among the plurality of networks from a transmission source network device via another relay device. When receiving a frame including each physical address of the transmission source and the destination, mask information for identifying each group is generated, and a group is determined from the mask information matching the information indicating the group in the virtual LAN identification information. Is specified.

According to the fourth aspect of the present invention, the physical addresses of the transmission source and the destination are indirectly transmitted from the transmission source network to which the transmission source network device is connected among the plurality of networks via another relay device. When receiving a frame including a group, mask information for specifying each group is generated, and the group is specified from the mask information matching the information indicating the group in the virtual LAN identification information. It is possible to easily determine to which group the frame received from the device belongs.

Further, according to the fifth aspect of the present invention, a virtual L
5. The AN system according to claim 3 or 4, wherein the relay device registers the relayed frame in association with a relationship between a reception port, a group corresponding to the port, and a source physical address. Is further provided.

According to the fifth aspect of the present invention, in the relay device, the receiving port,
Since the group corresponding to the port and the relationship of the physical address of the transmission source are registered in association with each other,
Port management for each group can be realized on the relay device.

Further, a virtual L according to the invention of claim 6 is provided.
The AN system according to claim 5, wherein the relay device relays the frame according to the content registered in the registration unit.

According to the sixth aspect of the present invention, the relay apparatus relays the frame in accordance with the registered content in which the relationship between the receiving port, the group corresponding to the port, and the physical address of the transmission source is associated. Therefore, it is possible to uniquely operate frame transmission between groups.

The virtual L according to the invention of claim 7
In the invention of claim 5, in the invention according to claim 5, when the physical address of the destination is not registered in the registration unit, the relay device is related to the group according to information indicating the group in the virtual LAN identification information. It is characterized in that frames are transmitted from all ports.

According to the seventh aspect of the present invention, when the physical address of the destination is not registered, all the ports related to the group are determined according to the information indicating the group in the virtual LAN identification information. Since the frame is transmitted from the destination, even when the physical address of the destination is unknown, it is possible to reliably transmit the frame to the destination with a minimum necessary relay operation.

The virtual L according to the eighth aspect of the present invention.
The AN system according to claim 5, wherein the second frame processing means is implemented when a physical address of a destination is registered in the registration means.

According to the present invention, the relay apparatus removes the virtual LAN identification information from the frame directly transmitted to the destination network only when the physical address of the destination is registered. Since the virtual LAN identification information is held for the frame transmitted indirectly to the destination network via another relay device, the frame transmission to a specific port can be realized according to the registered contents. is there.

The virtual L according to the ninth aspect of the present invention.
A network management method applied to an AN system is a virtual LAN system that connects one or a plurality of relay devices to a plurality of networks and logically groups and manages a relationship between network devices connected to the plurality of networks. A network management method applied to only when receiving a frame including each physical address of a source and a destination directly from a source network connected to a source network device among the plurality of networks, A first step of adding virtual LAN identification information for specifying a group to which the source network belongs and a port to which the source network is connected to the frame, and connecting a destination network device among the plurality of networks Frames directly to the network In this case, the virtual LAN identification information added in the first step is removed from the frame, and the virtual LAN identification information is indirectly connected to a network connected to a destination network device among the plurality of networks via another relay device. When transmitting a frame, a second step of holding the virtual LAN identification information added in the first step in the frame, and a virtual LAN added in the first step among frames relayed by the relay device. A third step of specifying a group to which the source network belongs and a port to which the source network is connected based on identification information.

According to the ninth aspect of the present invention, the group to which the source network belongs and the source network are connected only when a frame including the source and destination physical addresses is directly received from the source network. When the frame is added with virtual LAN identification information specifying the port to be transmitted and the frame is directly transmitted to the destination network, the virtual LAN identification information is removed from the frame, while the destination network is connected to the destination network via another relay device. When sending a frame indirectly, the virtual LA
Since the N identification information is held in the frame, and the frame to which the source network belongs and the port to which the source network is connected are specified based on the virtual LAN identification information in the frame relayed by the relay device. In addition, it is possible to easily specify a network where a failure has occurred from a transmission frame relayed by the relay device, thereby realizing network management for quickly achieving failure resolution.

Further, a network management method applied to a virtual LAN system according to the invention of claim 10 is as follows.
The invention according to claim 9 is characterized in that, in the first step, when virtual LAN identification information is not added to the received frame, the virtual LAN identification information is added.

According to the tenth aspect of the invention, when the virtual LAN identification information is not added to the received frame, the step of adding the virtual LAN identification information is performed, so that the virtual LAN identification information is added to the received frame. If no information is added, it is assumed that the port is directly connected to the network by a port, and that port information can be included in the virtual LAN identification information.

Further, a network management method applied to the virtual LAN system according to the invention of claim 11 is as follows.
The invention according to claim 9 or 10, wherein the relay device stores a group corresponding to each port, and
The method is characterized in that a group corresponding to the port is identified from a port at which the frame is received, and the virtual LAN identification information including information for identifying the identified group is generated.

According to the eleventh aspect of the present invention, when a frame including each physical address of the transmission source and the destination is directly received from the transmission source network connected to the transmission source network device, the frame is received. Since the step of identifying the group corresponding to the port from the port and generating the virtual LAN identification information including the information identifying the group is performed, the transmission frame is accurately associated with the group and the port, thereby , It is possible to transmit the correspondence between an accurate group and its port to another relay device.

Further, a network management method applied to the virtual LAN system according to the twelfth aspect of the present invention,
In the invention of claim 9 or claim 10, the first step comprises:
When a frame including each physical address of the source and destination is received indirectly via a relay device from a source network connected to a source network device among the plurality of networks, the respective groups are specified. And generating the mask information for identifying the group from the mask information that matches the information indicating the group in the virtual LAN identification information.

According to the twelfth aspect of the present invention, the physical addresses of the transmission source and the destination are indirectly transmitted from the transmission source network to which the transmission source network device is connected among the plurality of networks via another relay device. In the case of receiving a frame including the group, the mask information for specifying each group is generated, and the group is specified from the mask information matching the information indicating the group in the virtual LAN identification information. It is possible to easily determine to which group the frame received from the device belongs.

Further, a network management method applied to the virtual LAN system according to the invention of claim 13 is
13. The table according to any one of claims 9 to 12, wherein the relay device associates and registers a relationship between a receiving port, a group corresponding to the port, and a source physical address with respect to a frame to be relayed. And a fourth step of relaying a frame according to the contents registered in the table is further included.

According to the thirteenth aspect of the present invention, the receiving device, the group corresponding to the port,
In addition, since the step of relaying the frame is performed according to the registered contents in which the relationship between the physical addresses of the transmission sources is associated, it is possible to uniquely operate the frame transmission between the groups.

Further, a network management method applied to the virtual LAN system according to the invention of claim 14 is
14. The invention according to claim 13, wherein, if the destination physical address is not registered in the table, the fourth step is performed from all ports related to the group according to the information indicating the group in the virtual LAN identification information. It is characterized by transmitting a frame.

According to the fourteenth aspect of the present invention, when the physical address of the destination is not registered by the relay device, all the ports related to the group are transmitted from the virtual LAN identification information in accordance with the information indicating the group. Since the step of transmitting the frame is performed, even when the physical address of the destination is unknown, it is possible to reliably transmit the frame to the destination with the minimum necessary relay operation.

A network management method applied to a virtual LAN system according to the invention of claim 15 is
The invention according to claim 13 or 14, wherein the second step is performed when a physical address of a destination is registered in the table.

According to the fifteenth aspect, only when the physical address of the destination is registered by the relay device, the virtual LAN identification information is removed from the frame directly transmitted to the destination network. Since the process of holding the virtual LAN identification information for the frame indirectly transmitted to the destination network via another relay device is performed, the frame transmission to a specific port can be realized according to the registered contents. .

[0043]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a preferred virtual LAN system according to the present invention and a network management method applied to the virtual LAN system will be described below in detail with reference to the accompanying drawings.

First, a frame applied to the virtual LAN system according to one embodiment of the present invention will be described. FIG. 1 shows a virtual LA according to an embodiment of the present invention.
FIG. 2 is a diagram showing a frame format applied to the N system. The overall configuration of the frame shown in FIG. 1 is the same as the above-described conventional frame configuration, except that the destination MAC address, the source MAC address, the virtual LAN identifier, the data length, the data, and the frame check sequence (F
CS). The virtual LAN identifier is the virtual LAN group identification information (M
Bit) and port number information (M bits) representing the port number.

The virtual LA in the frame shown in FIG.
The N group identification information is a bit string forming a netmask, and is referred to identify a virtual LAN group. The port number information is a bit string that is not used for identification of the virtual LAN group, but is independently referred only to identify the port number of the bridge.

Next, the virtual LAN system will be described. FIG. 2 is a block diagram showing a configuration example of a virtual LAN system according to an embodiment of the present invention. For example, FIG. 2 shows a network management device 1 for managing a virtual LAN system, a plurality of networks N
A, NB, NC, ND, NE Relay devices 2 and 3 such as switch hubs for relaying the NE, networks NA, NB, NC,
Stations 4, 5, 6, 7 respectively connected to ND are shown.

FIG. 2 shows two relay devices 2 and 3 for explanation.
Is provided, but may be one, or three or more. Further, the numbers of the networks NA, NB, NC, ND, and NE connected to the relay devices 2 and 3 can be arbitrarily set.

The network management apparatus 1 includes, for example, as shown in FIG. 2, a transmission / reception unit 11, an ID processing unit 12, a netmask generation unit 13, a port identification unit 14, and the like. The transmission / reception unit 11 is connected to the network NE via a port (not shown), and transmits / receives frames to / from the relay devices 2 and 3 and other network devices on the network NE. The number of the transmission / reception units 11 is provided in accordance with the number of connected networks.

The ID processing unit 12 identifies a virtual LAN identifier in the frame shown in FIG. 1 and generates a virtual LAN identifier in a frame having no virtual LAN identifier. The ID processing unit 12
Performs attachment / detachment of a virtual LAN identifier in a frame communicated with the stations 4 to 7 connected to the relay apparatuses 2 and 3, respectively.

The net mask generator 13 generates a virtual L
Generate a netmask that is set in the AN identifier. The port specifying unit 14 specifies the source port using the virtual LAN identifier (net mask and port number) in the frame shown in FIG.

For example, as shown in FIG. 2, the relay device 2 includes transmission / reception units 21A, 21B, 21C, an ID processing unit 22
A, 22B, 22C, a netmask generator 23, address learning units 24A, 24B, 24C, an address learning table 25, a relay unit 26, and the like. Transceiver 21
A, 21B, and 21C are respectively connected to the networks NA, NB, and NE via ports (not shown), and transmit and receive frames to and from other relay devices and other network devices on the networks NA, NB, and NE. .

The ID processing units 22A, 22B and 22C identify a virtual LAN identifier in the frame shown in FIG. 1 and generate a virtual LAN identifier in a frame having no virtual LAN identifier. The ID processing units 22A, 22B, and 22C are connected to the relay device 2,
In the frames communicated with the stations 4 to 7 respectively connected to the station 3, the virtual LAN identifier is attached / detached.

The netmask generator 23 generates a virtual L
Generate a netmask that is set in the AN identifier. The address learning units 24A, 24B, and 24C transmit the source M of the frame received from each of the networks NA, NB, and NE.
The source MAC address is learned by identifying the AC address and the virtual LAN group.

The address learning table 25 is a memory for registering the contents learned by the address learning units 24A, 24B and 24C in the form of a table. Relay section 26
Is, if a frame is received from one network,
Virtual LAN from ID processing units 22A, 22B and 22C and address learning units 24A, 24B and 24C
The received frame (packet) is relayed to another network (one or more) based on the group information and the MAC address information.

The relay device 3 includes, as shown in FIG. 2, for example, transmission / reception units 31A, 31B, 31C, an ID processing unit 32
A, 32B, 32C, a netmask generator 33, address learning units 34A, 34B, 34C, an address learning table 35, a relay unit 36, and the like. Transmitting / receiving section 31
A, 31B, and 31C are connected to the networks NC, ND, and NE via ports (not shown), and transmit and receive frames to and from other relay devices and other network devices on the networks NC, ND, and NE. .

The ID processing units 32A, 32B and 32C identify the virtual LAN identifier in the frame shown in FIG. 1 and generate a virtual LAN identifier in a frame having no virtual LAN identifier. The ID processing units 32A, 32B, and 32C are connected to the relay device 2,
In the frames communicated with the stations 4 to 7 respectively connected to the station 3, the virtual LAN identifier is attached / detached.

The net mask generator 33 generates a virtual L
Generate a netmask that is set in the AN identifier. The address learning units 34A, 34B, and 34C transmit the frames M of the frames received from the networks NC, ND, and NE.
The source MAC address is learned by identifying the AC address and the virtual LAN group.

The address learning table 35 is a memory for registering the contents learned by the address learning units 34A, 34B, 34C in the form of a table. Relay section 36
Is, if a frame is received from one network,
Virtual LAN from ID processing units 32A, 32B and 32C and address learning units 34A, 34B and 34C
The received frame (packet) is relayed to another network (one or more) based on the group information and the MAC address information.

In the above virtual LAN system,
Network NA and Network NC are virtual L
AN α, and the network NB and the network ND are virtual LAN β. It is assumed that the network NE belongs to both the virtual LANs α and β.

Next, the flow of a frame in the virtual LAN system shown in FIG. 2 will be described. First, normal frame transmission will be described. FIG. 3 is a configuration diagram showing a virtual LAN system for explaining the operation of the relay apparatus 2 when transmitting a frame from the station 4 of the network NA to the station 6 of the network NC, and FIG. To Network N
FIG. 2 is a configuration diagram illustrating a virtual LAN system for explaining an operation of the relay device 3 when transmitting a frame to a station 6 of C.

First, a frame is transmitted from the station 4 to the relay device 2 via the network NA. In FIG. 3, in the relay device 2, when a transmission frame is received by the transmission / reception unit 21A, a unique virtual LAN identifier corresponding to the port receiving the frame is generated in the ID processing unit 22A. Is added to the frame. This ID processing unit 22A uses the virtual LA
The frame to which the N identifier is assigned is stored in the address learning unit 23A.
, Where learning of the receiving port, virtual LAN identifier and source MAC address is performed. The learning result is stored in the address learning table 25.

When the address learning is completed in this way,
The frame of interest is sent to the relay unit 26, where the relay destination is determined according to the contents of the address learning table 25. In this case, since the station 6 of the network NC is the destination, the relay device 2 outputs a frame to the network NE.

Therefore, the frame of interest is sent by the relay unit 26 to the ID processing unit 22C. This ID processing unit 22C
Then, in order to identify which virtual LAN group the frame of interest belongs to, a netmask is supplied from the netmask generator 23.

This netmask is compared with the netmask in the virtual LAN identifier in the frame of interest. As a result, if it matches the netmask generated by the netmask generator 23, the virtual LAN group corresponding to the netmask is identified as the virtual LAN group that communicates the frame of interest. Also, ID
In the processing unit 22C, the destination station 6 is the relay apparatus 2
Is not directly connected to the network, the operation of removing the virtual LAN identifier from the frame of interest is not performed, and the frame of interest is transmitted from the transmission / reception unit 21C to the network NE as it is.

The frame of interest is transmitted from the network NE to the relay device 3. In FIG. 4, when the transmission frame is received by the transmission / reception unit 31C, the relay device 3
In the D processing unit 32C, the netmask constituting the virtual LAN identifier in the received frame is compared with the netmask generated by the netmask generation unit 33 to identify which virtual LAN group it belongs to. The frame of interest is further transmitted to the address learning unit 34C, and learning of the reception port, the virtual LAN identifier, and the source MAC address is performed. The learning result is stored in the address learning table 35.

When the address learning is completed in this way,
The frame of interest is sent to the relay unit 36, where the relay destination is determined according to the contents of the address learning table 35. In this case, since the station 6 of the network NC is the destination, the relay device 3 outputs a frame to the network NC.

Then, the frame of interest is transmitted by the relay unit 36 to the ID processing unit 34A. This ID processing unit 34A
Then, in order to identify which virtual LAN group the frame of interest belongs to, a netmask is supplied from the netmask generator 33.

This netmask is compared with the netmask in the virtual LAN identifier in the frame of interest. As a result, if they match the netmask generated by the netmask generator 33, the virtual LAN group corresponding to the netmask is identified as a virtual LAN group that communicates the frame of interest.

In the ID processing section 34A, since the destination station 6 is directly connected to the relay device 3, an operation of removing the virtual LAN identifier from the frame of interest is performed, and the frame of interest removes the virtual LAN identifier. The data is transmitted from the transmission / reception unit 31A to the network NC in this manner.

A more specific operation of the above relay devices 2 and 3 will be described in detail. 5 and 6 show the relay devices 2 and 3
FIG. 7 is a diagram showing an example of registration of the address learning table according to this embodiment. When receiving the transmission frame from the network (step S1), the relay devices 2 and 3 confirm the port number at which the frame was received, the source MAC address and the virtual LAN identifier inserted in the received frame, The confirmed information is registered in the address learning table (step S2).

Here, the case of the relay device 2 will be described as an example.
Assuming that the port connected to the network NA is # 1, the port connected to the network NB is # 2, and the port connected to the network NE is # 3, the frame transmission between the networks NA and NC belonging to the group α , The network NE belongs to the group α.

Therefore, in the frame transmission from the station 4 of the network NA to the station 6 of the network NC, the source MAC address “ADR” is associated with the reception port # 1.
S1 "and the V-LAN group" α "are registered.In this response, since the data is received from the port # 3, the source MAC is associated with the reception port # 3.
The address “ADRS3” and the V-LAN group “α” are registered. Similarly, in frame transmission from the station 5 of the network NB to the station 7 of the network ND, the source MAC address “ADRS” is associated with the reception port # 2.
2 ”and the V-LAN group“ β ”are registered.

Returning to the description of the operation, if it is not confirmed in step S2 that the virtual LAN identifier has been assigned (step S3), the virtual LAN is transmitted based on the virtual LAN group from which the frame was transmitted.
Group identification information (net mask) is generated, port number information is generated by confirming the receiving port, and a virtual LAN identifier composed of the virtual LAN group identification information and the port number information is added to the received frame (step). S4). After that, the process proceeds to step S
Go to 5. If it is confirmed in step S2 that the virtual LAN identifier has been assigned (step S2).
3), the process proceeds to step S5.

In step S5, the destination MAC address is extracted from the received frame, and it is determined whether the destination MAC address exists in the address learning table. As a result, when the determination result that there is no existence is obtained, the process proceeds to step S6. On the other hand, when the determination result that there is an existence is obtained, the process proceeds to step S6.
Move to 7.

If the destination MAC address does not exist in the address learning table, the virtual LAN group cannot be specified. In step S6, the virtual LAN group identification information is extracted from the virtual LAN identifier in the frame, and the virtual LAN group identification is obtained. A process of transmitting a frame from the information to all ports belonging to the corresponding virtual LAN group is executed. Thus, the relay process ends.

On the other hand, if the destination MAC address exists in the address learning table, the virtual LAN group can be specified. Therefore, in step S7, it is checked whether the node of the destination MAC address is directly connected to itself. As a result, if it is not confirmed that the connection is directly established, the same node determination is required in another relay device, and the frame transmission is continued with the virtual LAN identifier left in the frame. Is done. That is, in the subsequent step S9, the destination MAC
The frame is transmitted from the port corresponding to the address.

On the other hand, if it is confirmed that the connection is directly established, it is not necessary to perform node determination by another relay device, and the virtual LAN identifier is removed from the frame in the subsequent step S8. Then, the process proceeds to step S9, and the frame is transmitted from the port corresponding to the destination MAC address.

Further, a case where the station 4 has a failure in the above-described frame transmission from the station 4 to the station 6 will be described. FIG. 8 shows a partially failed virtual LAN
FIG. 1 is a configuration diagram showing a virtual LAN system for explaining frame transmission in the system. In FIG. 5, the frame transmitted from the station 4 on the network NA is transmitted to the network NC via the network NE in the above-described flow.
In addition to being transmitted to the upper station 6, it is also transmitted to the network management device 1 on the network NE.

It should be noted that it is possible to specify from a situation such as a communication delay or a disconnection that a failure has occurred in network-related communication. Here, it is known that there is a failure in communication between networks. Therefore, when a transmission frame is received by the network management device 1, a process for specifying the presence or absence of a failure and the network having a failure (specifically, a port) is executed based on the transmission frame.

In the network management device 1, the frame transmitted from the network NE is received by the transmission / reception unit 11. This received frame is sent to the ID processing unit 12. The ID processing unit 12 is supplied with a netmask from the netmask generation unit 13 to identify to which virtual LAN group the frame of interest belongs.

This netmask is compared with the netmask in the virtual LAN identifier in the frame of interest. As a result, if it matches the netmask generated by the netmask generation unit 13, the virtual LAN group corresponding to the netmask is identified as a virtual LAN group that communicates the frame of interest.

As described above, in the ID processing unit 12, the process of extracting the netmask in the virtual LAN identifier and performing group collation has been performed. However, the port identification unit 14 has performed the port number information in the virtual LAN identifier. And the port number is specified from the port number information. This port number indicates the physical port of the relay device 2 that connects the network NA in which a failure has occurred. As a result, the network NA, that is, the station 4 is determined from the physical port of the relay device 2 having the failure.

A more specific operation of the network monitoring device 1 will be described in detail. FIG. 9 is a flowchart illustrating the operation of the network monitoring device. When the transmission frame is received from the network NE (step S11), the network monitoring device 1 extracts the virtual LAN group identification information from the virtual LAN identifier of the received frame, and determines the received frame based on the virtual LAN group identification information. Virtual LA
The frames belonging to the N group are identified (step S
12).

Further, port number information is extracted from the virtual LAN identifier, and a port number is specified from the port number information (step S13). Then, the station of the network related to the node of the port number is notified as a failure point by, for example, a display or the like (step S14).

Next, the above-mentioned relay device (the relay device 2,
A switch hub will be described as an example of 3).
Here, a description will be given with the system configuration of the same size as the conventional system in comparison with the conventional system. FIG. 10 is a configuration diagram illustrating an example of a virtual LAN system when a switch hub is applied as a relay device.

FIG. 10 shows a virtual LAN system in which a plurality of switch hubs 8B, 8C, 8D and 8E are connected to a switch hub 8A. Switch hub 8A
Are, for example, five ports # 1, # 2, # 3, # 4, # 5
And each port # 1, # 2, # 3, # 4, # 5
Are connected to the switch hubs 8B, 8C, 8D, 8E and the network management device 1. Also, switch hub 8
Each of B, 8C, 8D, and 8E has seven ports, and each has a switch hub 8A connected to port # 7.

In the above-described virtual LAN system, there are four virtual LAN groups as in the prior art. The group names are A, B, C, and D as in the related art. In the switch hub 8B, ports # 1, # 2, #
3, # 4, # 5, and # 6 respectively include nodes A1 (group A), B1 (group B), C1 (group C),
A2 (group A), D1 (group D), and A3 (group A) are assigned. In the switch hub 8C, the ports # 1, # 2, # 3, # 4, # 5, and # 6 respectively have nodes A4 (group A), B2 (group B), C2 (group C), and D2 (group D). ), D
3 (group D) and C3 (group C) are assigned.

In the switch hub 8D, the ports # 1, # 2, # 3, # 4, # 5, and # 6 are connected to the nodes A5 (group A), B3 (group B), and C4, respectively.
(Group C), B4 (Group B), D4 (Group D), and A6 (Group A) are assigned. In the switch hub 8E, ports # 1, # 2, # 3, #
Nodes A7 (group A), B5 (group B), C5 (group C), B6
(Group B), D5 (Group D), and D6 (Group D) are assigned.

In the virtual LAN system described above, communication is performed using frames having the format shown in FIG. At this time, among the virtual LAN identifiers, the virtual LAN
The group is identified, and the port number is identified from the port number information.

In FIG. 10, nodes B1 to B
When a frame is transmitted to the switch hub 8A (the transmission path is indicated by a dashed line in FIG. 10), the frame is received at the port # 2 (node B1) of the switch hub 8B, and the received frame is transmitted to the switch hub 8A. Port # 2 from port # 7 of switch hub 8C via ports # 1 and # 2
(Node B2).

When a frame is transmitted from the node B6 to the node B2 (the transmission path is shown by a two-dot chain line in FIG. 10), the frame is received at the port # 4 (node B6) of the switch hub 8E. The received frame is transmitted from port # 7 of switch hub 52 to port # 2 (node B) via ports # 4 and # 2 of switch hub 8A.
Sent to 2).

In this embodiment, since the virtual LAN identifier shown in FIG. 1 is inserted in the frame, the frame transmitted from the node B1 includes the port # 7 of the switch hub 8B to the port of the switch hub 8A. #
1, the port number information representing the port # 2 of the switch hub 8B is inserted by the above-described algorithm. Similarly, the frame transmitted from the node B6 is also transmitted from the port # 7 of the switch hub 8E to the switch hub 8
When the data is relayed to the port # 1 of A, the port number information indicating the port # 4 of the switch hub 8E is inserted by the above-described algorithm.

Thus, the network management device 1 can identify the source of the frame from the port number information inserted in the virtual LAN identifier of the frame sent from the switch hub 8A. That is, it is possible not only to determine a trouble spot on the virtual LAN system but also to easily confirm a double address (MAC address) which has conventionally been a problem. If you manage this all the time,
Along with determining the point of failure, it is possible to take early measures to prevent communication errors due to erroneous MAC address sharing.

As described above, according to this embodiment, in the system configuration shown in FIG. 2, in relay apparatuses 2 and 3, only the frames directly received from the transmission source network belong to the group to which the transmission source network belongs. And a virtual LAN identifier that specifies the port to which the source network is connected, and removes the virtual LAN identifier from frames directly transmitted to the destination network, while indirectly connecting to the destination network via another relay device. Virtual LAN
Processing for retaining the identifier is performed.

In the network management device 1, a process for specifying a group to which the source network belongs and a port to which the source network is connected, based on the virtual LAN identifier, out of the frames relayed by the relay device. Will be implemented. As a result, it is possible to easily specify the network where the failure occurs, from the transmission frames relayed by the relay devices 2 and 3.
It is possible to realize network management for achieving fault resolution quickly.

Further, in the relay devices 2 and 3, when the virtual LAN identifier is not added to the received frame, the virtual LAN identifier is added. Therefore, the virtual LAN identifier is added to the received frame. If not, it is assumed that the port is directly connected to the network by the port, and that port information can be included in the virtual LAN identifier.

When a frame including the source and destination physical addresses is directly received from the source network to which the source network device is connected, a group corresponding to the port is received from the port on which the frame was received. Is generated and a virtual LAN identifier including information for specifying the group is generated, so that a transmission frame is associated with a correct group and its port. This makes it possible to transmit the correspondence between the correct group and its port to another relay device.

When a frame including each physical address of a source and a destination is indirectly received from a source network to which a source network device is connected among a plurality of networks via another relay device, Since a netmask for specifying the group is generated and the group is specified from the netmask matching the information indicating the group in the virtual LAN identifier, the frame received from another relay device is It is possible to easily determine whether the transmission is a frame transmission.

In the relay devices 2 and 3, the relation between the receiving port, the group corresponding to the port, and the transmission source MAC address is related to the relayed frame and tabulated, so that the port management for each group is performed. Can be realized on the relay device.

The relay devices 2 and 3 relay the frame in accordance with the registered contents in which the relationship between the receiving port, the group corresponding to the port, and the source MAC address is associated with reference to the address learning table. With this configuration, it is possible to uniquely operate frame transmission between groups.

In the relay devices 2 and 3, if the destination physical address (meaning of the transmission source MAC address) is not registered in the address learning table, the group is determined in accordance with the information indicating the group in the virtual LAN identifier. Since the frames are transmitted from all the ports related to, the frames can be reliably transmitted to the destination by the minimum necessary relay operation even when the physical address of the destination is unknown.

In the relay devices 2 and 3, only when the physical address of the destination (meaning of the source MAC address) is registered in the address learning table, a virtual L-frame is not transmitted from the frame directly transmitted to the destination network.
Since the AN identifier is removed and the virtual LAN identifier is retained for the frame indirectly transmitted to the destination network via another relay device, the frame is sent to a specific port according to the registered contents of the address learning table. Can be realized.

In the above-described embodiment, the functions of the relay device and the network management system are described separately. However, the present invention is not limited to this, and the functions of the network management system are incorporated in the relay device. Needless to say, this may be done.

Although the present invention has been described with reference to the embodiment, various modifications are possible within the scope of the present invention, and these are not excluded from the scope of the present invention.

[0105]

As described above, according to the first aspect of the present invention, in the relay device, the group to which the source network belongs and the source network are connected only to frames directly received from the source network. Virtual LAN identification information specifying the port to be transmitted to the destination network, and removing the virtual LAN identification information from the frame directly transmitted to the destination network.
Since the group to which the source network belongs and the port to which the source network is connected are specified based on the virtual LAN identification information, it is possible to easily identify the network in which the failure has occurred from the transmission frame relayed by the relay device. Thus, there is an effect that a virtual LAN system capable of realizing network management for promptly solving a failure can be obtained.

According to the invention of claim 2, according to claim 1,
In the invention of the present application, the virtual LA is added to the received frame.
Virtual LAN when N identification information is not added
Since the identification information is added, if the virtual LAN identification information is not added to the received frame, it is assumed that the frame is directly connected to the network by a port, and the information of the port is included in the virtual LAN identification information. There is an effect that a virtual LAN system capable of performing the above can be obtained.

According to the third aspect of the present invention, the first aspect
In the invention of the second aspect, when a frame including the physical addresses of the transmission source and the destination is directly received from the transmission source network connected to the transmission source network device, the port corresponding to the port from which the frame was received corresponds to the port. Since the virtual LAN identification information including the information for identifying the group and identifying the group is generated, the transmission frame is associated with the correct group and its port, and thereby, the transmission frame can be accurately transmitted to other relay devices. There is an effect that a virtual LAN system capable of transmitting the correspondence between a group and its port can be obtained.

According to the invention of claim 4, according to claim 1,
In the second aspect, when a frame including each physical address of a source and a destination is indirectly received from a source network to which a source network device is connected among a plurality of networks via another relay device, Since the mask information for specifying each group is generated and the group is specified from the mask information that matches the information indicating the group in the virtual LAN identification information, the frame received from another relay device is This has the effect of providing a virtual LAN system that can easily determine which group is involved in frame transmission.

According to the invention of claim 5, according to claim 3,
In the invention of the fourth aspect, in the relay apparatus, the relayed frame is registered in association with the relationship between the receiving port, the group corresponding to the port, and the physical address of the transmission source. There is an effect that a virtual LAN system capable of realizing management on the relay device is obtained.

Further, according to the invention of claim 6, according to claim 5,
In the invention of the above, the relay device relays the frame in accordance with the registered content in which the relationship between the receiving port, the group corresponding to the port, and the physical address of the transmission source is associated, so that the frame transmission between the groups is performed. There is an effect that a virtual LAN system that can be uniquely operated is obtained.

According to the invention of claim 7, according to claim 5,
According to the invention, when the physical address of the destination is not registered, the frame is transmitted from all the ports related to the group according to the information indicating the group in the virtual LAN identification information. In addition, there is an effect that a virtual LAN system capable of reliably transmitting a frame to a destination with a minimum necessary relay operation even when the physical address of the destination is unknown is obtained.

According to the invention of claim 8, according to claim 5,
In the invention, the relay apparatus removes the virtual LAN identification information from the frame directly transmitted to the destination network only when the physical address of the destination is registered, and transmits another relay apparatus to the destination network. Since the virtual LAN identification information is held for the frame transmitted indirectly through the network, the effect of obtaining a virtual LAN system capable of realizing frame transmission to a specific port according to the registered contents is obtained. Play.

According to the ninth aspect of the present invention, the group to which the source network belongs and the source network are only used when a frame including the source and destination physical addresses is directly received from the source network. When virtual LAN identification information specifying a port to be connected is added to the frame and the frame is directly transmitted to the destination network, the virtual LAN identification information is removed from the frame, while the destination network is connected to the destination network via another relay device. When sending a frame indirectly, the virtual L
Since the AN identification information is held in the frame and the port to which the transmission source network is connected and the group to which the transmission source network belongs are specified based on the virtual LAN identification information in the frame relayed by the relay device. A virtual LA that can easily identify a network where a failure has occurred from a transmission frame relayed by a relay device, thereby realizing network management for promptly solving a failure.
There is an effect that a network management method applied to the N system can be obtained.

According to the tenth aspect of the present invention, in the ninth aspect of the present invention, a virtual L is added to the received frame.
Virtual LA when no AN identification information is added
In the case where the virtual LAN identification information is not added to the received frame, it is assumed that the port is directly connected to the network by the port, and the information of the port is added to the virtual LAN identification information. There is an effect that a network management method applied to a virtual LAN system that can be included can be obtained.

According to the eleventh aspect of the present invention, in the ninth or tenth aspect, a frame including each physical address of a source and a destination is directly received from a source network connected to a source network device. In the case where the frame is received, the group corresponding to the port is identified from the port where the frame is received, and the virtual LAN identification information including the information for specifying the group is generated. Ports are associated with each other, thereby providing an effect that a network management method applied to a virtual LAN system capable of transmitting the correspondence between an accurate group and its port to another relay device can be obtained. .

According to the twelfth aspect of the present invention, in the ninth or tenth aspect of the present invention, a source network to which a source network device is connected among a plurality of networks is indirectly transmitted via another relay device. If you receive a frame containing the source and destination physical addresses in
Since the mask information for specifying each group is generated and the group is specified from the mask information that matches the information indicating the group in the virtual LAN identification information, the frame received from another relay device is used. There is an effect that a network management method applied to a virtual LAN system that can easily determine which group is involved in frame transmission can be obtained.

According to a thirteenth aspect of the present invention, in any one of the ninth to twelfth aspects of the present invention, the relay device includes a receiving port, a group corresponding to the port, and a source physical address. Is carried out in accordance with the registered contents associated with the group, so that a network management method applied to a virtual LAN system capable of uniquely operating frame transmission between groups can be obtained.

According to the invention of claim 14, in the invention of claim 13, when the physical address of the destination is not registered by the relay device, the relay device according to the information representing the group in the virtual LAN identification information. Since the frame is transmitted from all ports related to the group, it is applied to a virtual LAN system that can reliably transmit a frame to the destination with the minimum necessary relay operation even when the physical address of the destination is unknown. There is an effect that a network management method can be obtained.

Further, according to the invention of claim 15, in the invention of claim 13 or 14, only when the physical address of the destination is registered by the relay device, the frame transmitted directly to the destination network is not transmitted. Virtual L
Since the step of removing the AN identification information and holding the virtual LAN identification information for the frame indirectly transmitted to the destination network via another relay device is performed, the frame to the specific port is registered according to the registered contents. There is an effect that a network management method applied to a virtual LAN system capable of realizing transmission can be obtained.

[Brief description of the drawings]

FIG. 1 shows a virtual LAN according to an embodiment of the present invention.
FIG. 2 is a diagram showing a frame format applied to the system.

FIG. 2 shows a virtual LA according to an embodiment of the present invention.
FIG. 1 is a block diagram illustrating a configuration example of an N system.

FIG. 3 is a configuration diagram illustrating a virtual LAN system for explaining an operation of a first relay device when transmitting a frame.

FIG. 4 is a configuration diagram illustrating a virtual LAN system for explaining an operation of a second relay device when transmitting a frame.

FIG. 5 is a flowchart illustrating an operation of the relay device according to the embodiment.

FIG. 6 is a flowchart illustrating the operation of the relay device according to the embodiment.

FIG. 7 is a diagram illustrating an example of registration of an address learning table according to the embodiment;

FIG. 8 is a configuration diagram showing a virtual LAN system for explaining the operation of the network management device when transmitting a frame.

FIG. 9 is a flowchart illustrating an operation of the network management device according to the embodiment.

FIG. 10 is a configuration diagram illustrating an example of a virtual LAN system when a switch hub is applied as a relay device.

FIG. 11 is a diagram illustrating a frame format used in a conventional virtual LAN system.

FIG. 12 is a configuration diagram showing an example of a conventional virtual LAN system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Network management apparatus 2, 3 relay apparatus 11 Transmission / reception part 12 ID processing part 13 Net mask generation part 14 Port identification part 21A, 21B, 21C, 31A, 31B, 31C Transmission / reception part 22A, 22B, 22C, 32A, 32B, 32C I
D processing unit 23, 33 Netmask generation unit 24A, 24B, 24C, 34A, 34B, 34C Address learning unit 25, 35 Address learning table 26, 36 Relay unit

Claims (15)

[Claims] 1. A network management apparatus for logically grouping and managing a relationship between one or a plurality of relay devices connecting a plurality of networks and network devices connected to the relay devices and connected to the plurality of networks. And wherein only when the relay device receives a frame including each physical address of a source and a destination directly from a source network connected to a source network device among the plurality of networks, First frame processing means for adding, to the frame, virtual LAN identification information for specifying a group to which a source network belongs and a port to which the source network is connected; and a destination network device among the plurality of networks. When transmitting frames directly to the connected network, A second frame processing unit for removing the virtual LAN identification information added by the one frame processing unit from the frame, the network management device comprising: A virtual LAN system, wherein a group to which the source network belongs and a port to which the source network is connected are specified based on the added virtual LAN identification information. 2. The apparatus according to claim 1, wherein the first frame processing means adds the virtual LAN identification information when no virtual LAN identification information is added to the received frame. Virtual LA
N system. 3. The relay device stores a group corresponding to each port, and the first frame processing means identifies the group corresponding to the port from the port at which the frame was received, and identifies the group. The virtual LAN system according to claim 1, wherein the virtual LAN identification information including information for specifying a specified group is generated. 4. The first frame processing means indirectly transmits a physical address of a source and a destination from a source network connected to a source network device among the plurality of networks via another relay device. When receiving a frame including a group, mask information for specifying each group is generated, and a group is specified from mask information that matches information indicating the group in the virtual LAN identification information. The virtual LAN system according to claim 1. 5. The relay device, for a frame to be relayed, a receiving port, a group corresponding to the port,
4. The apparatus according to claim 3, further comprising a registering unit for registering the relationship between the physical addresses of the transmission sources.
Or the virtual LAN system according to 4. 6. The virtual LAN system according to claim 5, wherein the relay device relays a frame according to the content registered in the registration unit. 7. When the physical address of the destination is not registered in the registration unit, the relay device transmits a frame from all ports related to the group according to information indicating the group in the virtual LAN identification information. The virtual LAN system according to claim 5, wherein the transmission is performed. 8. The virtual L function according to claim 5, wherein said second frame processing means is executed when a physical address of a destination is registered in said registration means.
AN system. 9. Network management applied to a virtual LAN system in which one or a plurality of relay devices are connected to a plurality of networks, and a relationship between network devices connected to the plurality of networks is logically grouped and managed. The method, wherein the source network belongs only when receiving a frame including each physical address of a source and a destination directly from a source network connected to a source network device among the plurality of networks. A first step of adding virtual LAN identification information for specifying a group to be connected and a port to which the source network is connected to the frame, and directing a frame to a network connected to a destination network device among the plurality of networks. Is transmitted, it is added in the first step. In the case where the virtual LAN identification information is removed from the frame and the frame is indirectly transmitted via another relay device to a network connected to a destination network device among the plurality of networks, Added virtual L
A second step of retaining AN identification information in the frame; and a group to which the transmission source network belongs, based on the virtual LAN identification information added in the first step, of the frame relayed by the relay device. Third to specify the port to which the source network is connected
A network management method applied to a virtual LAN system, comprising: 10. The virtual LAN according to claim 9, wherein in the first step, the virtual LAN identification information is added when the received frame has no virtual LAN identification information added thereto. Network management method applied to the system. 11. The relay device stores a group corresponding to each port, and the first step identifies the group corresponding to the port from the port at which the frame was received, and identifies the identified group. The network management method applied to a virtual LAN system according to claim 9, wherein the virtual LAN identification information including information for specifying the virtual LAN system is generated. 12. The first step includes, indirectly, a physical address of a source and a destination via a relay device from a source network connected to a source network device among the plurality of networks. When receiving a frame, generating mask information for identifying each group, and identifying a group from mask information that matches information representing the group in the virtual LAN identification information. A network management method applied to the virtual LAN system according to 9 or 10. 13. The relay apparatus is provided with a table for associating a relationship between a receiving port, a group corresponding to the port, and a physical address of a transmission source with respect to a frame to be relayed, and registers the frame in the table. The network management method according to any one of claims 9 to 12, further comprising a fourth step of relaying a frame according to the performed content. 14. The method according to claim 4, wherein, if the destination physical address is not registered in the table, a frame is transmitted from all ports related to the group in accordance with information indicating the group in the virtual LAN identification information. The network management method applied to the virtual LAN system according to claim 13, wherein the transmission is performed. 15. The network management applied to the virtual LAN system according to claim 13, wherein the second step is performed when a physical address of a destination is registered in the table. Method.