JPH09307579A - Multiport relay device and network equipment - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] One network device includes a plurality of virtual LANs.
Multiport relay device can belong to a virtual L
(EN) Provided are a multi-port relay device and a network device that do not require storage / search of all MAC addresses for AN. A multi-port relay device (101) sets a network device (111) connected to a port as an address in a virtual LAN of the network device (M).
Virtual LAN address that can be replaced with AC address 10
Assign 00. The assigned network device 111 uses this address as the address of its own station in the virtual LAN and uses it for the frame instead of the MAC address. The multi-port relay device 101 sends a frame to a virtual L
Relay based on AN address 1000.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-port relay device and a network device for grouping network devices on a network to form a virtual LAN, and in particular, one network device has a plurality of virtual LANs.
Multiport relay device can belong to a virtual L
The present invention relates to a multi-port relay device and a network device that do not require storage and retrieval of all MAC addresses for AN.

[0002]

2. Description of the Related Art In a network in which network devices are interconnected by a multiport relay device,
A so-called virtual LAN is known in which network devices are divided into groups according to the ports to which the network devices are connected and the MAC addresses of the network devices, and communication is performed only between the network devices included in the group. Therefore, a conventional multi-port relay device having a virtual LAN function divides network devices into virtual LAN groups according to ports and MAC addresses, and relays only between network devices included in the virtual LAN group. There is.

The MAC address is ISO / IEC 8802-3 (CSMA /
CD) or ISO / IEC 8802-5 (Token Ring), etc., a network adapter that is an address unique to the hardware of the network device and is incorporated in the network device as a physical network interface. In addition, it is fixedly held by a ROM (Read Only Memory) or the like.

[0004]

As described above, the MAC address is unique to the network device and cannot be given from others. Further, since the relay can be performed by using this MAC address as the destination or source of the frame, it is impossible to communicate using an address other than the MAC address.

Conventionally, when constructing a virtual LAN, a network device is virtual LA by such a MAC address.
Since it is divided into N groups, one network device cannot belong to more than one virtual LAN group.

Further, in the multi-port relay device having the virtual LAN function, since the relay is performed only between the network devices included in the virtual LAN group, the virtual LA is used.
It is necessary to store the MAC addresses of all network devices belonging to the N group. When relaying frames in such a virtual LAN, the virtual LAN
It is necessary to search the MAC address of the network device belonging to the group, compare it with the MAC address included in the frame, and then perform the relay.

Therefore, an object of the present invention is to solve the above-mentioned problems, one network device can belong to a plurality of virtual LANs, and the multi-port relay device stores and retrieves all MAC addresses for the virtual LAN. It is to provide a multi-port relay device and a network device that do not require.

[0008]

In order to achieve the above object, the multi-port relay device of the present invention can replace a network device connected to a port with a MAC address as an address in the virtual LAN of the network device. A virtual LAN address is assigned.

The virtual LAN address is a flag indicating that this address is a local address of a MAC address, a flag indicating that this address is a virtual LAN address, and a virtual LAN to which a network device having this address belongs. The identification number of the group, the identification number of the multi-port relay device to which the network device having this address is connected, and the end network device identification number that identifies the network device having this address may be included.

When the virtual LAN address is used as the source or destination MAC address of the frame, even if relay is performed based on the multiport relay device identification number and the termination network device identification number included in this virtual LAN address. Good.

Further, the network device is a virtual LA that can be replaced with a MAC address from the multiport relay device.
Received N address and assigned this address to virtual LA
This is the address of its own station in N.

When performing communication in the virtual LAN, the virtual LAN address may be used in place of the frame source or destination MAC address.

[0013]

An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

According to the present invention, a network device is provided with a virtual LAN address that can be replaced with a MAC address, and this virtual LAN address is the source or destination MA of a frame.
It can be used for the C address. This virtual LAN address may be considered as a virtual MAC address that can be arbitrarily determined independently of the hardware of the network device, separately from the MAC address unique to the hardware of the network device. Therefore,
Since one network device can have a plurality of virtual LAN addresses and each virtual LAN address can be used in place of the MAC address in that virtual LAN, one network device can have a plurality of virtual LAN addresses.
Will be able to belong to.

The multi-port relay device assigns a virtual LAN address to a network device, and for a frame having this virtual LAN address as a source or destination, the multi-port relay device identification number and end network device identification included in the virtual LAN address. Relay based on the number.

The network device receives the virtual LAN address from the multi-port relay device, and performs communication using the virtual LAN address instead of the source or destination MAC address of the frame.

Since the virtual LAN address of the multi-port relay device includes the multi-port relay device identification number and the termination network device identification number, the multi-port relay device to which the network device is connected can be known and the network device can be specified. . Therefore, the relay can be performed based on the multiport relay device identification number and the termination network device identification number, and all MAs can be relayed.
There is no need to store the C address or search and compare the MAC address.

Here, FIG. 1 shows a configuration example of the virtual LAN address.

As shown, virtual LAN address 1
000 is ISO / IEC 8802-3 (CSMA / CD) or ISO / IEC 88
It has a 48-bit MAC address structure defined by 02-5 (Token Ring). Here, each bit is given a number from 1 to 48 from the left side of the drawing.

The second bit of the virtual LAN address 1000 is a flag indicating that this address is a local address of the MAC address. That is, according to the above standard, the second bit is Universal / Local (Universal / L
ocal) Identification bit 1001 and this bit is “0”
Then, this MAC address is a universal address (global address), and if this bit is "1", this MAC address is a local address. In the virtual LAN address, the second bit is set to "1" to always indicate the local address.
This ensures that the virtual LAN address does not overlap with the global address that is uniquely held by the network device.

The third bit of the virtual LAN address 1000 is used as a flag for indicating that this address is a virtual LAN address, that is, a virtual LAN address identification bit 1002. If this bit is "1", this address is a virtual LAN address.

The fields from the 7th bit to the 16th bit of the virtual LAN address 1000 are used as a virtual LAN group identification number (virtual LAN identification number) 1003. The value set in this field makes it possible to identify the virtual LAN group to which the network device having this virtual LAN address belongs. Also,
A frame having this virtual LAN address as a source or destination MAC address can identify the virtual LAN group used for communication. By using the fields from the 7th bit to the 16th bit, a maximum of 102
Up to 4 virtual LAN groups can be set.

The fields from the 18th bit to the 32nd bit of the virtual LAN address 1000 are used as the multiport relay device identification number 1004. The multi-port relay device identification number 1004 is a number assigned to the multi-port relay device in advance so that the administrator will not duplicate it. This virtual L depends on the value set in this field.
It is possible to identify the multi-port relay device to which the network device having the AN address is connected.

The fields from the 33rd bit to the 48th bit of the virtual LAN address 1000 are used as the terminal network equipment identification number 1005. The terminal network device identification number 1005 is a number for identifying the network device, and is assigned by the multi-port relay device to the network device connected to itself so as not to overlap with other network devices.

The multi-port relay device holds the correspondence between the terminal network device identification number 1005 and the port to which the network device is connected. As a result, the multiport relay device can relay a frame addressed to a network device to a port to which the network device is connected.

FIG. 2 shows a configuration example of a network using the multi-port relay device and network equipment according to the present invention. As shown in the figure, this network has two multi-port relay devices 101 and 102, which are connected to each other. Further, network devices 111 and 112 are connected to the respective ports of the multiport relay apparatus 101, and network devices 113 and 114 are connected to the respective ports of the multiport relay apparatus 102.

In this network, two virtual L's of virtual LAN group # 1 and virtual LAN group # 2
An AN group exists and network devices 111 and 11
Since 4 belongs to the virtual LAN group # 1 and the network devices 111, 112, 113 belong to the virtual LAN group # 2, the network device 111 belongs to both the virtual LAN group # 1 and the virtual LAN group # 2. Become.

In the present invention, such a virtual LAN is used.
In order to realize the above configuration, each network device is assigned a virtual LAN address by the multiport relay device to which it is connected. The specific procedure will be described by taking the case of the network device 111 as an example.

FIG. 3 is an example of a frame sequence used in the allocation process for realizing such a virtual LAN configuration. The network device 111 uses the multiport relay device 1 to which its own station is connected when the power is turned on.
A request frame 321 for requesting allocation of the virtual LAN address used in the virtual LAN group # 1 is transmitted to 01. The multiport relay apparatus 101 that has received this request frame 321 creates a virtual LAN address used by the network device 111 in the virtual LAN group # 1 as in the configuration example of FIG.
A response frame 331 having this virtual LAN address as the response content is returned to the network device 111. continue,
The network device 111 is the multiport relay device 10
1, the request frame 322 for requesting the allocation of the virtual LAN address used in the virtual LAN group # 2 is transmitted. Upon receiving the request frame 322, the multi-port relay device 101 similarly creates a virtual LAN address used by the network device 111 in the virtual LAN group # 2, and sends a response frame 332 having this virtual LAN address as the response content to the network device. Return to 111.

In the case of the network device 114, or in the case of the network devices 112 and 113, the above frame sequence is performed only for the virtual LAN group # 1 or # 2.

By performing the allocation processing by such a frame sequence, one network device has one to a plurality of virtual LAN addresses. Since these virtual LAN addresses can be replaced with MAC addresses, the network device has a virtual LAN address that can be used as a MAC address in addition to the hardware-specific MAC address that it originally has, and it is as if there are multiple MAC addresses. As if it had an address.

Next, the communication operation of the network device in the virtual LAN will be described.

When transmitting a frame to a single network device or all network devices in a virtual LAN group, the network device corresponds to the virtual LAN group among one to a plurality of virtual LAN addresses assigned to itself. Use the virtual LAN address as the source MAC address. In addition, the virtual LAN address corresponding to the virtual LAN group of a single destination or all network devices is used as the destination LAN address.

The virtual LA of the destination network device
The N address may be acquired in advance by using a protocol for acquiring a MAC address such as ARP protocol.

When the virtual LAN address is used for the MAC address of the network device when the frame is received, after determining the virtual LAN group from the virtual LAN identification number included in the virtual LAN address, the network device This frame is passed to the communication entity of the upper protocol which uses the network interface of this virtual LAN.

Next, the virtual LAN of the multiport relay device
The relay process in will be described.

FIG. 4 shows an example of the flow of relay processing. When the frame arrives at the port in step 401, the multiport relay device reads the destination MAC address in step 402. In step 403, if the destination MAC address is a local address and the virtual LA
If the N address identification bit is "1", it is determined to be a virtual LAN address. If the destination MAC address is the virtual LAN address, then in step 404 this virtual LA
The multiport relay device identification number included in the N address is referred to. If this multi-port relay device identification number matches the multi-port relay device identification number of the own device, the network device that is the destination of the frame can be determined to be the network device connected to the own device, so step 405. Then, referring to the end network device identification number included in this virtual LAN address, from the correspondence relationship between the end network device identification number and the port to which the network device is connected, which is held by this multiport relay device. , Relay the frame to the corresponding port. If the multi-port relay device identification number included in the virtual LAN address does not match the multi-port relay device identification number of its own device, in step 406, the frame is relayed to the adjacent multi-port relay device. Destination MA
If the C address is not the virtual LAN address, a normal frame relay process is performed in step 407.

As described above, in the multi-port relay device, the relay process in the virtual LAN group can be performed based on the multi-port relay device identification number and the termination network device identification number included in the virtual LAN address. In the prior art, the multiport relay device is a virtual LA.
The MAC addresses of all the network devices belonging to the N group are stored, the MAC addresses of the network devices belonging to the virtual LAN group are searched and compared with the MAC addresses included in the frame. If it is large, a very large storage capacity is required, and the search / comparison process becomes enormous. In the case of the present invention, regardless of the scale of the network, each multiport relay device is connected to its own device and the correspondence relationship between the multiport relay device identification number of the adjacent multiport relay device and its connection port. It is only necessary to hold the correspondence relationship between the terminal network device identification number of the network device and its connection port. Therefore, the multi-port relay device is much lighter in storage capacity and search / comparison processing than conventional ones.

[0039]

The present invention exhibits the following excellent effects.

(1) Since one network device can belong to a plurality of virtual LANs, the virtual LAN can be used easily.

(2) The multiport relay device is a virtual LAN
Since it is not necessary to store and retrieve all MAC addresses for
The burden is reduced and the processing time is shortened.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a virtual LAN address showing an embodiment of the present invention.

FIG. 2 is a configuration diagram of a network using the multi-port relay device and the network device of the present invention.

FIG. 3 is a diagram of a frame sequence used for allocation processing according to the present invention.

FIG. 4 is a flowchart of a relay process according to the present invention.

[Explanation of symbols]

 101, 102 Multi-port relay device 111, 112, 113, 114 Network device 1000 Virtual LAN address 1001 Universal / local identification bit 1002 Virtual LAN address identification bit 1003 Virtual LAN group identification number 1004 Multi-port relay device identification number 1005 Termination network device identification number

Claims (5)

[Claims] 1. In a multi-port relay device having a plurality of ports and relaying a frame between the ports, a network device connected to the port is replaced with a MAC address as an address in the virtual LAN of the network device. A multi-port relay device, which allocates possible virtual LAN addresses. 2. The virtual LAN address belongs to a flag indicating that this address is a local address of a MAC address, a flag indicating that this address is a virtual LAN address, and a network device having this address. It is characterized in that it includes the identification number of the virtual LAN group, the identification number of the multi-port relay device to which the network device having this address is connected, and the end network device identification number for identifying the network device having this address. The multiport relay device according to claim 1. 3. When the virtual LAN address is used as the source or destination MAC address of a frame, relay is performed based on the multiport relay device identification number and the termination network device identification number included in this virtual LAN address. The multiport relay device according to claim 2, wherein 4. A network device which is connected to a port of a multi-port relay device and communicates via the multi-port relay device, wherein the multi-port relay device is connected to the MA device.
A network device, which receives a virtual LAN address that can be replaced with a C address, and uses this address as an address of its own station in the virtual LAN. 5. The virtual LAN address is used in place of a frame source or destination MAC address when performing communication on the virtual LAN.
The listed network equipment.