WO2006093321A1

WO2006093321A1 - Node, network, correspondence creating method, and frame transferring program

Info

Publication number: WO2006093321A1
Application number: PCT/JP2006/304420
Authority: WO
Inventors: Masaki Umayabashi; Kazuo Takagi; Daisaku Ogasahara; Nobuyuki Enomoto; Youichi Hidaka; Atsushi Iwata
Original assignee: Nec Corporation
Priority date: 2005-03-04
Filing date: 2006-03-01
Publication date: 2006-09-08
Also published as: CN101171802B; JP4780340B2; CN101171802A; JPWO2006093321A1

Abstract

A node, a network, a correspondence creating method and a frame transferring program for achieving, in EoE technique, an optimum path transfer, thereby avoiding the traffic concentration to any particular link so as to improve the throughput of the whole network. A frame switching part (230) comprises a frame analyzing part (300) for analyzing the input frame type or the like; a table search part (330) for acquiring frame rewriting information and output port information; a forwarding table storing part (340) for managing a frame output port; a MAC learning part (350) for performing a MAC address learning; an EoE-MAC learning part (360) for learning a relationship between a MAC address and a EoE-MAC address; an STP control part (380) for performing a spanning tree process; and so on.

Description

Description Node, network, correspondence creation method and frame transfer program

The present invention relates to a node, network, correspondence creation method and frame transfer program in an EoE (Etherne®) over Ethernet (R)) network, and more particularly to a node, network and correspondence creation method for frame transfer optimization. And a frame transfer program. Background art

In recent years, Wide Area Ethernet (R) VPN Service (Wide Area Ether), which has developed Ethernet (R) technology widely used in conventional LANs over wide area networks, is attracting attention as an inexpensive corporate data service. . Wide-area Ether inherits the advantages of conventional Ethernet (R) technology such as ease of use of plug and play and low cost, but the MAC address of the user terminal passes through the core network, so the switch is processed. There is a problem that the number of MAC addresses to be used is enormous. In other words, if the amount of MAC address processing in the core switch (MAC address learning processing, address search processing during frame transfer, etc.) becomes a bottleneck, or if the number of MAC addresses accommodated in the core switch is limited, the MAC address accommodated in the network There is a problem that the number of addresses (the number of accommodated user terminals) is limited.

In order to solve such problems, Non-Patent Document 1 proposes a technique called EoE. In addition to Non-Patent Document 1, there are similar technologies such as MAC in MAC technology discussed in IEEE 802.1. However, since the issues described below are common, non-patent documents are here. 1 will be described.

Figure 48 shows an example of a wide area Ether network. Wide-area Ether's network consists of edge switches Ε5, 66, 、 7, Ε8 that accommodate user terminals T5, T6, Τ7, and Τ8, and a core switch C that does not accommodate user terminals and performs only relay operations. 3 and C 4 In the wide area Ethernet service using conventional Ethernet (R) technology,

In 48, if 10,000 user terminals are connected to each edge switch, the core switch must process 40,000 MAC addresses. On the other hand, with E o E technology, each edge switch has a MAC address that is valid only within the network (hereinafter referred to as E o E—MAC address) and is connected under its own switch. When transferring a frame from a user terminal into the network, encapsulate with E o E—MAC address. In FIG. 48, E o E—MA C address e 5, e 6, e 7, and e 8 are set for the edge switches E 5, E 6, E 7, and E 8, respectively.

Next, the frame format will be described. Figure 49 shows normal Ethernet

(R) Frame 4300 format. Ethernet (R) frame 4

300 includes a destination MA C address 4310, a source MA C address 4320, a Type 4330, a payload 4340, and an FCS (Frame Check Sequence) 4350.

In contrast, E o E— frames encapsulated with MAC addresses (hereinafter referred to as

The format of EoE frames is shown in Figure 50. Figure

As shown in 50, EoE frame 4400 is an Ethernet (R) frame 4

E o E of destination edge switch before 440—MAC address 4410 (destination E o E—MAC address), E o E of source switch that is the source—MAC address 44 20 (source E o E—MAC address) ), Type 4430 is added, and the frame is encapsulated by adding FCS 4450 after the Ethernet (R) frame 4440. Note that the Ethernet (R) frame 4 encapsulated here

440 is the Ethernet (R) frame received from the user terminal 4300 to FC

54350 is deleted.

Figure 51 shows the format when a VLAN tag is added to the Ethernet (R) frame from the user terminal. An Ethernet (R) frame 4500 with a VLAN tag is composed of a destination MAC address 4310, a source MAC address 4320, a VLAN tag 4510, a Type 4330, a pay slot 4340, and an FCS 4350. The Ethernet (R) frame 4440 in Figure 50 has a VLAN Tagged Ethernet (R) Frame 4500 with FCS 4350 deleted may be stored.

Also, the E o E frame 4400 may be configured with a VLAN tag, in which case the destination E o E—MAC address 4410, source E o E—MAC address 4420, VLAN 4510, It consists of Type 4430, Ethernet (R) frame 4440, and FCS 4450.

Returning to the description of FIG. 48, when edge switches E5 to E8 receive Ethernet (R) frames from user terminals T5 to T8, they are encapsulated with E o E-MAC address and sent to the core network side. By forwarding, a frame with E o E—MAC address is forwarded to the core switches C 3 and C4. Therefore, the core switches C3 and C4 need only process the MAC addresses for the number of edge switches in the network. In the example in Fig. 48, the number of edge switches is 4, so each core switch C3, C4 should process 4 MAC addresses.

In the previous example of the existing Ethernet (R) technology, when 10,000 user terminals are connected to each edge switch, 40 thousand MAC addresses had to be processed. By using, you can process four MAC addresses. In this way, with EoE technology, the core switch only supports the conventional MAC address transfer, and the number of MAC addresses processed by the core switch is equal to the number of edge switches regardless of the number of MAC addresses accommodated in the network. This has the effect of being able to reduce the number of MAC addresses, and is a technology that can be extended to large-scale networks.

On the other hand, with Ethernet (R) technology, if no action is taken, the frame will continue to run around the loop if there is a loop configuration in the network, especially if the broadcast frame continues to run. there's a possibility that. To avoid this, even if there is a physical loop configuration in the network, the Spanning Tree Protocol (Spanning Tree Protocol) can be used to create a loop-free network by logically eliminating the loop. In the following, this technology is referred to as STP.This technology is defined in IEEE802.1D.) And its high-speed operation version of the high-speed scanning tree protocol (R api Spanning Tr ee P rotocol. Hereinafter referred to as RSTP. This technology is defined in IEEE 802.1 w. ) Is often used.

Ding? When STP technology is used, a loop-free configuration is achieved when any port on the loop configuration is in a blocking state (a state in which main signal frames are not transmitted or received). Taking the network in Fig. 48 as an example, there is a loop configuration between the edge switch E7, the core switch C3, and the core switch C4Z edge switch E8. ) Loop 3 becomes free when 3 is in the blocking state.

However, when such STP and RSTP technologies are used, frames cannot be transferred on the link connected to the blocking port, so when transferring frames between switches, they cannot be transferred using the shortest path (minimum number of hops). In the example of Fig. 48, when frame transfer is performed from user terminal T6 to user terminal T5, port p3 of edge switch E5 is in the blocking state, so edge switch E6 → edge switch E5 It cannot be transferred on the route, but is transferred on the route of the edge switch E 6 → core switch C 4 → edge switch E 8 → edge switch E 7 → core switch C 3 → edge switch E 5 and arrives at the user terminal T 5.

As a technology to solve this problem, Non-Patent Document 2 uses Mu 1 tip 1 e STP (hereinafter referred to as MS TP) technology that can manage multiple VLAN IDs, and each edge switch is self-switching. An STP / RS TP tree is created that is the forwarding path that is the root node, and the STP / RSTP tree is the forwarding path for frames destined for the edge switch that is the root node of each STPZR STP tree. For the link that is active in the STPZRSTP tree (link that does not include a blocking port), the link that minimizes the link cost from the root node is selected. It becomes.

FIG. 53 shows an example in which the method of Non-Patent Document 2 is used for the frame transfer from the user terminals T 6 to T 5 described above with reference to FIG. In FIG. 53, the frame transfer from user terminal T 6 to T 5 is performed using the ST PZRSTP tree in which edge switch E 5 is the root node (edge switch E 7, from £ 8 to £ 5). Is also transferred using the ST PZRS TP tree in which edge switch E5 is the root node). Accordingly, the frame from the user terminal T 6 arrives at the user terminal T 5 via the edge switch E 6 and the edge switch E 5. In this way, transfer between each node can be performed with the shortest path.

In order to perform such transfer, Non-Patent Document 2 performs the following processing. When transferring between edge switches, the node ID set for each edge switch is stored in the VL AN tag of the Ethernet (R) frame, and each edge switch and co- switch switches the frame based on the ID.

In Figure 53, node IDs = gll, gl 2, gl 3, and g 14 are assigned to edge switches E 5, E 6, E 7, and E 8 respectively, and edge switch E 6 to edge switch E 5 are assigned. For forwarding, VLAN ID = g 1 1 stored in the VLAN tag is stacked in the frame at edge switch E 6 (this VLAN flag is referred to as the “forging tag”), and it is the same at edge switch E 6. Frames are transferred in the direction of edge switch E5 based on ending flag -g 1 1.

In the forwarding table of each switch, the output port for the forwarding tag value is managed, and the STPZRSTP tree in which the edge switch having the node ID equal to the forwarding tag value is the root node is used as the output port. The port number of one root port (the port state at that time is the forwarding state indicating the transfer enabled state) is set. Here, both the forwarding tag value (destination edge switch node ID) and the STP / RSTP tree identification ID (VLAN ID) are stored in the VLAN tag, and the values are the same.

In Figure 53, the node ID of edge switch E 5 is g 1 1, and the identification ID (V LAN ID) of the STPZRSTP tree where edge switch E 5 is the root node is also g 1 1, which is stored in the VLAN tag. . Therefore, the setting in the forwarding table reflects the port information of the STPZRSTP tree identified by the same identifier as the value for the forwarding tag. In Figure 53, for each switch, the output port to the forwarding tag g 1 1 reflects the STPZRSTP tree point information of VLAN ID = g 1 1.

Non-Patent Document 1 Ando (PoweredCom), "LAN Switch Technology-Redundancy Method and latest technology ~ ", Internet we ek 2003, http: Z / www. Ni c. A d. Jp / en / materi 1 s / iw / 2003 Z proceedi ng sZ i nd e x. / www. ni c. ad.j / ja Zm ateria 1 s / iw / 2003 / proceedings / T 14-2.pdf, p. 42- 57

Non-Patent Document 2 Takahashi et al., “Proposal of Next Generation Ethernet (G) Architecture G〇E (G 1 oba 1 Optical Ethernet (R)) — (2) High-efficiency routing and high-speed protection”, 2002 IEICE Society Conference, B— 7— 1 1

Figure 54 shows whether applying the optimal route transfer technology of Non-Patent Document 2 to the EoE technology of Non-Patent Document 1 described above can solve the problem of optimal route transfer in the EoE technology. It explains using.

As in Non-Patent Document 2, in E o E technology, an STPZRSTP tree is created in which each edge switch is the root node. Since MS TP technology is used, the identifier of each STPZRSTP tree is VLAN ID. In FIG. 54, the VLAN ID of the STPZRSTP tree that is rooted at the edge switch E 5 is g 1 1. In EoE technology, frame transfer is performed based on the EoE-MAC address as described above.

In FIG. 54, the EoE-MAC address of edge switch E5 is e5, and the frame addressed to edge switch E5 is transferred based on EoE-MAC address e5. Here, when the output port is set by the method of Non-Patent Document 2, each switch does not know the STP / RSTP tree identifier (V LAN ID) corresponding to the EoE—MAC address, and E o E— The output port for the MAC address cannot be determined. As described above, there is a problem that the optimum route transfer cannot be performed in the EoE technology by simply applying the technology of Non-Patent Document 2 as it is to the EoE technology. Disclosure of the invention

The object of the present invention is to avoid the concentration of traffic to a specific link by realizing optimal route forwarding in EoE technology, and to reduce the throughput of the entire network. It is to improve.

In order to achieve the above object, the present invention is configured as follows.

The node according to claim 1, wherein the node in the network transfers a data frame sent from a source terminal to a destination terminal, wherein each node in the network includes an identifier of a node to which the destination terminal is connected, and the destination A correspondence relationship between identifiers of a spanning tree having a node connected to a terminal as a root node is maintained, an identifier of a node connected to the destination terminal and an identifier of the spanning tree are added to the data frame, and Based on the port information of the spanning tree, the output port for the node to which the destination terminal is connected is determined from the correspondence relationship, and the data frame is transferred.

The node according to claim 2, wherein the node to which the transmission source terminal is connected uses the identifier of the node to which the destination terminal is connected as a destination address in a data frame received from the transmission source terminal as the transmission source address. The identifier of the node to which the source terminal is connected is added, the frame is transmitted, and the data frame is transferred on the spanning tree based on the identifier of the added node. .

The node according to claim 3, when determining an output port for a node connected to the destination terminal, out of the spanning tree ports, a port that is a root port and in a forwarding state, The output port of the unicast frame, and the assigned port that is in the forwarding or learning state is the output port of the broadcast cast frame.

5. The node according to claim 4, wherein each node holds a table in which a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree is set in advance.

6. The node according to claim 5, wherein a correspondence relationship between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree is included in information included in a predetermined control frame transferred on the network in the creation of the spanning tree. It is generated from The node according to claim 6, wherein the identifier of the node to which the destination terminal is connected is obtained so that the identifier of the node to which the destination terminal is connected is obtained by performing a predetermined operation on the identifier of the spanning tree. The identifier of the node to which the destination terminal is connected is obtained by performing a predetermined calculation on the identifier of the spanning tree acquired from the received data frame, and the identifier of the node to which the destination terminal is connected and the spanny It is characterized in that the correspondence relationship between the identifiers of the mapping tree is acquired.

The node according to claim 7, wherein the node stores a table that records a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree, and performs the processing of the spanning tree. Based on the notification information from the control unit, the identifier of the node to which the destination terminal is connected is acquired from the notified identifier of the spanning tree, and the output port for the node to which the acquired destination terminal is connected is the spanning tree. A table control unit that sets to a port acquired from one control unit and writes to the forwarding table, and holds an output port for the identifier of the node to which the destination terminal is connected in the foraging table. Table and broadcast cast for the spanning tree identifier or VPN identifier A table for holding the force port to feature that rank.

The node according to claim 8, wherein the table control unit manually sets a table that records a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree.

The node according to claim 9 transfers a predetermined control frame on a spanning tree after the processing of the spanning tree is completed, and the table control unit receives the destination from the information stored in the received control frame. Obtaining a correspondence relationship between the identifier of the node to which the terminal is connected and the identifier of the spanning tree, and storing the correspondence relationship between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree. Features.

The node according to claim 10, wherein a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree is obtained from information stored in a predetermined control frame transferred on the spanning tree. The table control unit obtains the identifier of the node to which the destination terminal connects the acquired correspondence information and the spanning. It is characterized in that it is stored in a table that records the correspondence of tree identifiers. The node according to claim 11, wherein the table control unit calculates an identifier of a node connected to the destination terminal from the acquired identifier of the spanning tree, and an identifier of the node connected to the destination terminal and the node The correspondence relationship between the identifiers of the spanning tree is acquired, and the acquired correspondence relationship information is stored in a table that records the correspondence relationship between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree.

12. The node according to claim 12, wherein a node connected to the destination terminal stores the identifier of the own node as a transmission source address, and adds data storing an identifier of a spanning tree in which the own node is a root node. It is characterized by sending a data frame.

14. The node according to claim 13, wherein a node other than the node connected to the destination terminal receives the port that has received the data frame transmitted from the node connected to the destination terminal as the destination terminal. It is an output port for a node to be connected. 15. The node according to claim 14, wherein when an identifier of a node connected to the destination terminal of a data frame received from the source terminal is unknown, the node stores an identifier of the own node as a source address, A table search unit that decides to create and send a data frame with data that stores the identifier of the spanning tree that will be the node, and a node identifier that is stored in the source address of the received data frame And a MAC learning unit that uses an output port corresponding to a combination of a child and an identifier of a spanning tree as a reception port of the reception frame.

The node according to claim 15, wherein the source terminal that transmits and receives a data frame and the destination terminal form a network that stores an identifier of the spanning tree when a network based on another protocol is formed. Overnight, data storing an identifier for identifying a network based on the other protocol is added to the data frame.

The node according to claim 16 is a table that holds a network identifier based on another protocol for a data frame reception port, or a data frame. It has a table holding network identifiers according to other protocols for the receiving port and the identifier of the scanning tree.

The node according to claim 17, wherein the source terminal that transmits / receives a data frame and the destination terminal form a network based on another protocol, and the data frame is In the case of a unicast frame, data for storing an identifier for identifying a network according to another protocol is added to the data frame together with the data for storing the identifier for the scanning tree. When the spanning tree is used as a transfer path and the data frame is a multicast frame or a broadcast frame, data for storing an identifier for identifying a network based on the other protocol is added to the data frame. Using a transfer route set for a terminal belonging to a network based on another protocol. It is characterized by that.

The node according to claim 18 is a table holding network identifiers of other protocols for receiving ports of data frames, or a network of other protocols for receiving ports of data frames and spanning tree identifiers. A table for storing work identifiers, and when the data frame is a unicast frame, the table search unit searches for a network based on another protocol together with data for storing the identifier of the spanning tree. Determines creation and transmission of a data frame to which data for storing an identifier is added, and identifies the network based on the other protocol when the data frame is a multicast frame or a broadcast frame. Add data to store identifiers And determining the creation and transmission of the data frame.

The node according to claim 19, wherein the network based on the other protocol is V P N.

The nomad according to claim 20, wherein the identifier of the node to which the destination terminal is connected is an E o E-MAC address.

(Work)

According to the present invention, in a node to which a transmission source node is connected, an identifier of a node to which a destination terminal is connected and a node to which the destination terminal is connected are routed to a data frame to be transmitted. A data frame with a spanning tree identifier added as a node is transmitted using the spanning tree as a route, and the relay node uses the identifier of the node connected to the destination terminal and the node connected to the destination terminal as the root node. The data frame is transferred based on the relationship between the node and the identifier of the spanning tree added to the data frame and the correspondence relationship.

In this way, by transferring the data frame based on the correspondence,

Even in E o E technology, data frame transfer on the optimal route is possible.

According to the present invention, in a network composed of nodes, a spanning tree in which a node connected to the destination terminal is the root node is used as a transfer path to the destination terminal. By maintaining the correspondence between the identifier of the node connected to the node and the identifier of the spanning tree, the shortest path is formed between all the nodes connected to the destination terminal, and all data frames sent from the source terminal are transmitted. It is possible to transfer to the destination terminal by the shortest route.

This eliminates traffic bias in the network, reduces the possibility of congestion, and makes it possible to efficiently use the network bandwidth, thereby improving the throughput of the entire network. it can. Brief Description of Drawings

FIG. 1 is a network model diagram of the wide area Ether of the present invention.

FIG. 2 is a configuration diagram of the switch of the present invention.

FIG. 3 is a configuration diagram of the frame switching unit according to the first embodiment of the present invention.

FIG. 4 is a configuration diagram of the forwarding table storage unit of the present invention.

FIG. 5 is a MAC table of the present invention.

FIG. 6 is a MA C / E o E—MA C table of the present invention.

FIG. 7 is a broadcast table of the present invention.

FIG. 8 is an STP port state management table of the present invention.

FIG. 9 is a VL AN / E o E—MAC management table of the present invention. FIG. 10 is an E oE-MACZVLAN management table of the present invention.

FIG. 11 is an STP port state management table of each switch according to the present invention.

FIG. 12 is a folding table of the edge switch E 5 in the first embodiment of the present invention.

FIG. 13 is a foraging table of the core switch C 5 according to the first embodiment of the present invention.

FIG. 14 is a folding table of the edge switch E 7 in the first embodiment of the present invention.

Figure 15 shows an example of an Ethernet (R) frame.

FIG. 16 shows an example of an E o E frame.

FIG. 17 is a configuration diagram of a frame switching unit according to the second embodiment of the present invention.

Figure 18 shows the B PDU format.

Fig. 19 shows the format of BPDU Root Idenifier. FIG. 20 is a configuration diagram of the frame switching unit according to the third embodiment of the present invention.

FIG. 21 shows an example of the configuration of E o E—MAC address.

FIG. 22 is a configuration diagram of the frame switching unit according to the fourth embodiment of the present invention.

FIG. 23 is a folding table of the edge switch E 5 according to the fourth embodiment of the present invention.

FIG. 24 is a forking table of the core switch C 5 according to the fourth embodiment of the present invention.

FIG. 25 is a foraging table of the edge switch E 7 in the fourth embodiment of the present invention.

Figure 26 is an example of an Ethernet (R) frame.

Figure 27 is an example of an EoE broadcast frame.

FIG. 28 is an example of an E o E broadcast frame.

FIG. 29 is another network model diagram of the wide area Ether of the present invention. FIG. 30 is a configuration diagram of a frame switching unit according to the fifth embodiment of the present invention.

FIG. 31 is another configuration diagram of the forwarding table storage unit of the present invention. FIG. 32 is a port ZV P N table of the present invention.

FIG. 33 is another VPN / portable table of the present invention.

FIG. 34 is a port V PN table of the present invention.

FIG. 35 is another VPN / port table of the present invention.

Figure 36 shows an example of an E o E frame with a V L AN tag.

FIG. 37 is another network model diagram of the wide area Ether of the present invention.

FIG. 38 is a configuration diagram of the frame switching unit according to the sixth embodiment of the present invention.

FIG. 39 is an example of the forwarding table of each switch in the sixth embodiment of the present invention.

FIG. 40 is an example of an E o E broadcast frame.

Figure 41 shows an example of an E o E frame with a V L AN tag.

FIG. 42 is a flowchart showing an outline of the frame transfer procedure in the first embodiment of the present invention.

FIG. 43 is a flowchart showing an overview of the forwarding table update procedure according to the first embodiment of the present invention.

FIG. 44 is a flowchart showing an overview of the association processing procedure between the E o E-MAC address and the V LAN ID according to the second embodiment of the present invention.

FIG. 45 is a flowchart showing an outline of the association processing procedure between the E o E-MAC address and the V LAN ID according to the third embodiment of the present invention.

FIG. 46 is a flowchart showing an outline of the forwarding table update procedure according to the fourth embodiment of the present invention.

FIG. 47 is a flowchart showing an outline of the broadcast frame transfer processing procedure in the sixth embodiment of the present invention.

Figure 48 is a network model diagram of a conventional wide area Ether.

Figure 49 shows the Ethernet (R) frame format. Figure 50 shows the format of the E o E frame.

Figure 51 shows the format of an Ethernet (R) frame with V L A N.

Figure 52 shows the format of an E o E frame with a VLAN tag.

Figure 53 is a network model diagram of a conventional wide area Ether.

Fig. 54 is a network model diagram of a conventional wide area Ether.

200: Switch, 201-204: IF, 21 1-22: PHY, 2 21-224: MAC, 230: Frame switching unit, 240: Memory, 250: CPU, 260: Console IZ0, 300: Frame Analysis unit, 3 10, 3010, 3810: Frame rewriting unit, 320: Frame transfer unit, 3

30, 3030, 3830: Table search section, 340, 3040, 3 840: Fording table storage section, 350: MAC learning section, 360:

E o E—MAC learning part, 370: Control frame distribution part, 3 80, 1

780, 2280: STP control unit, 390, 1790, 2090, 2 290: Table control unit, 395: Setting control unit, 341, 1203, 1303, 14

03, 2301, 2304, 2401, 2404, 2501, 2504: MAC-table, 342, 1204, 1404, 1406, 2302, 2 3 05, 2

502, 2505: MAC / E o E—MAC table, 343, 1 2 05, 1

305, 1405, 2303, 2403, 2503, 3901, 39 1 1, 39

21: Broadcast table, 344: Table write controller, 345: Table read controller, 1 100, 1201, 130 1, 1401: STP port status management table, 900, 1202, 1302, 1402: VLAN / E

0 E—MAC management table, 1000: E o E—MA CZV L AN management table, 1 500, 2600, 4300, 5040: Ethernet (R) frame,

1600, 4400: E o E frame, 1800: BBDU, 1801: MAC-DA field, .1802: MAC-SA field, 1803, 5 110: VLAN tag field, 1804: Type field, 1805: B PDU Parame evening area, 1806: FCS field, 181 1: Protocol I dentifier field, 1812: P rotoc o 1—Version—I denfier field, 1813: BPDU—Type field, 1814: F 1 ags field, 181 5: Rot one I dentifier field, 1816: Root one Path one Cost field, 1817 : Bridge I I dentifier field, 1818: Port I I dentifier field, 18 19: Message one A ge field, 1820: Max-A ge field, 182 1: He 1 1 o one T i me field, 1822: Forest rding 1 D e 1 ey field, 18141: Priority field, 1 8 14 2: Fixed value field, 18143: MAC—Ad dress field, 2 100: E o E— MAC address, 2700, 2800, 400.0: EoE broadcast frame, 3046: VPN management table, 30461, 3

0463, 3902, 3922: Port / V P N table, 30462, 30

464, 3903, 3923: VPN / point table, 3600, 4600, 4100: E o E frame with VL AN tag, 4910: Destination MAC address, 4920: Source MAC address, 4930, 5030: Type, 494

0: Payload, 4950, 5050: FCS, 50 10: Destination E o E—MA C address, 5020: Source EoE—MAC address, 4500: Ethernet frame with VL AN tag, 4510: VLAN tag, C 1 , C2, C3, C4: Core switch, E1, E2, E3, E4, E5, E6, E7, E8: Edge switch, Tl, Τ2, Τ3, Τ4, Τ5, Τ6 , Τ7, Τ

8: User terminal, el, e2, e3, e4, e5, e6, e7, e8: EoE — MAC address, tl, t2, t3, t4, t5 T 6, t 7, t 8: MAC address, gl, g 3: VLAN ID, pl, p 2, p 3... Port number BEST MODE FOR CARRYING OUT THE INVENTION

(First embodiment)

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a physical network configuration example to which the present invention is applied.

The edge switches (nodes) in Fig. 1 are compatible with EoE technology, E1, E2, E.3, E4 The core switches (nodes) C 1 and C 2 are switches compatible with the existing Ethernet (R) technology, and both have the functions according to the present invention in addition to the conventional functions. The following connections are used between the switches.

Edge switch E 1 port p 3 and Edge switch E 2 port p 1, Edge switch E 1 port p 2 and Core switch C 1 port p 1, Core switch C 1 port p 2 and Edge switch E 3 Port p 1, edge switch E 3 port p 3 and edge switch E 4 port p 2, edge switch E 4 port p 1 and port switch C 2 port p 3, core switch C 2 Port p 1 and port switch 2 of edge switch E 2, core switch C 1 port p 3 and core switch C 2 port p 2 are connected to each other.

Each edge switch connects user terminals as follows.

Edge switch E 1 port p 1 user terminal T 1, edge switch E 2 port — p 3 user terminal T 2, edge switch E 3 port p 2 user terminal T 3, edge switch E 4 port User terminal T 4 is connected to port p 3.

A typical example of frame forwarding in such a network is

—The Ethernet (R) frames transmitted from the terminals T 1 to T 4 are capsulated into the MAC frames at the edge switches Ε 1 to Ε 4, and E o E—MAC at the core switches C 1 and C 2 Assuming that transfer at the address is performed, and that E o E—MAC frame encapsulation is canceled at the edge switch E 1 to E 4 on the destination user terminal side and transferred to the destination user terminal T1 to T 4 To do.

In the first embodiment of the present invention, in order to realize the optimum route transfer in the Ε0Ε technology, each of the edge switches Ε1 to Ε4 is a switch based on STP / RS TP whose own node is the root node. Each banning tree is created, and each switch in the network identifies the spanning tree based on each STPZRSTP. VL AN ID and EoE MAC address of edge switches E1 to E4 that are the root nodes of the spanning tree Holds the association with.

Then, the STP control unit, which will be described later, sets an output port for the EoE-MAC address with reference to the association based on the port information of the sub-banding tree based on STPZRSTP. The outline of the operation in the present embodiment will be described below with reference to FIG. 42 and FIG.

The outline of the frame transfer procedure in the switch of this embodiment is as shown in the flowchart of FIG.

VLAN tagged E oE—Receive MAC frame (Step A—1). The EoE—MAC address that indicates the node to which the destination terminal is connected and the VLAN ID that indicates the spanning tree with the node to which this destination terminal is connected as the root node are obtained, and the forwarding table (described later) is obtained. Refer to and obtain the output port corresponding to this EoE—MAC address and VLAN ID (Step A—2). Step A— Output the VLAN tagged E o E—MAC frame from the output port acquired in Step 2 (Step A—3).

In the node to which the source terminal is connected, the E o E-MAC address indicating the node to which the source terminal is connected, the E o E-MAC address indicating the node to which the destination terminal is connected, The VLAN ID that indicates the spanning tree whose root node is the node to which this destination terminal is connected, and each field (destination E o E—MAC address field) of the Ethernet (R) frame with VLAN binding received from the source terminal Field, source E o E — MAC address field, VLAN tag field).

In the node to which the destination terminal is connected, the destination E oE—MAC address field, source E o E—MAC address field, VLAN tag, etc. are deleted from the received frame. Obtain the address and the MAC address of the destination terminal, and send this frame to the destination terminal.

The outline of the procedure for updating the forwarding table in the present embodiment is as shown in the flowchart of FIG. '

Each switch receives VLAN ID (Spanning Tree Protocol ID) and changed port information (described later) when the STP port status (described later) changes (Step B Do)

Referring to the corresponding table, obtain the E o E—MAC address corresponding to the VLAN ID in Step B—1 (Step B—2). Update the forwarding table by rewriting the output port corresponding to the E o E— MAC address obtained in Step B—2 to the notification port from the Spanning Tree Protocol (Step B-3).

The detailed contents of the frame transfer procedure and the forwarding table update procedure will be clarified in the following explanation of each component and its operation.

The configuration of the edge switches E 1 to E 4 and the core switches C 1 and C 2 will be described with reference to FIG.

The switch 200 in FIG. 2 is a configuration diagram common to the edge switches E 1 to E 4 and the core switches C 1 and C 2.

Switch 200 is a PHY (PHY s i c a l) 2 1 1, 212, 213, 2

14, MAC (Media Ac s s s s Control) 221, 222, 223, 224, frame switching unit 230, memory 240, CPU 250, and console I / O 260.

PHY2 1 1, 212, 213, 214 are interfaces that perform access at the physical layer, which is the lowest layer of the OS I reference model.

Reference numerals 223 and 224 denote interfaces for executing access in the MAC layer that is a lower sublayer of the data link layer of the OS I reference model.

PH Y 21 1, 212, 213, 214 is connected to IF (interface part) 201, 202, 203, 204, respectively, and MAC 22 1, 222, 223, 224 is connected to PHY 21 1, 212, 213, 214 Connected, MAC 221,

A frame switching unit 230 is connected to 222, 223, and 224.

Ethernet (R) frames input from IF 20 1 202, 203, and 204 are frame switching units 230 via PHYs 21 1, 212, 213, 214 and MACs 22 1, 22 2, 223, 224, respectively. In the frame switching unit 230, an appropriate output IF is determined by the operation described later, and the IF is passed through the MAC 221, 222, 223, 224 and PHY 21 1, 212, 213, 2 14 respectively. Output to 201, 202, 203, 204. The CPU 250 and the memory 240 store a program for controlling the operation of the frame switching unit 230 and necessary data. 6304420

19 Controls the ring 230. The console I ZO 260 is an external interface for setting management for each part in the device.

The switch 200 of the present invention can be realized by software by executing the program for executing each of the above-described components on the CPU 250 of the computer processing apparatus as well as realizing the operation by hardware. Can do. This program is stored in the memory 240, which is a recording medium such as a magnetic disk or a semiconductor memory, loaded from the memory 240 to the CPU 250, and controls its operation, thereby realizing each function of each component described above. .

FIG. 3 shows a detailed configuration of the frame switching unit 230.

Frame switching unit 230 consists of frame analysis unit 300, frame rewriting unit 3

10, Frame transfer unit 320, Table search unit 330, Forwarding table storage unit 340, MAC learning unit 350, E o E-MAC learning unit 3

60, control frame distribution part 370, 3? Control unit 380, table control unit 39

0, and a setting control unit 395.

As described above, the frame switching unit 230 has a function of determining the output IF of the Ethernet (R) frame input from the MAC 221 to 224 and transferring it to the MAC 221 to 224 connected to the predetermined IF. .

When switch 200 is edge switch E1-E4, input / output frame type is Ethernet (R) frame 4300 in Fig. 49 or Ethernet (R) frame 4500 with VL AN tag in Fig. 51. EoE frame

4400 or E o E frame 4600 with VLAN tag is output.

Or E o E frame 4400 or E o E frame with V LAN tag 460

0 is input, and Ethernet (R) frame 4300 or Ethernet (R) frame 4500 with VL AN tag is output. Or, for both input and output frames, E o E frame 4400 or VL AN tagged E o E — MAC frame 460

It may be 0.

When the switch 200 is the core switch C1, C2, the input / output frame type is the EoE frame 4400 or the EoE frame 4600 with VLAN tag for both the input / output frames. Hereinafter, each component of the frame switching unit 230 will be described. The frame analysis unit 300 analyzes frames input from MAC 221 to 224, and performs normal Ethernet (R) frame 4300 or Ethernet (R) frame with VLAN tag 4500 or E o E— MAC frame 4400 or VL E o E with AN tag — When the main signal data frame is a MAC frame 4600, the header information, frame type information, and input port information are transferred to the table search unit 330 and the MAC learning unit 350.

If the input frame is E o E—MAC frame 4400 or E o E—MAC frame 4600 with a VLAN tag, the above information is also transferred to E o E—MAC learning unit 360. Also, the entire frame or the payload portion is transferred to the frame rewriting unit 310.

If the input frame is a control frame such as BP DU, the entire frame is transferred to the control frame distribution unit 370.

Frame rewrite section 310 rewrites the main signal data frame received from frame analysis section 300 when an instruction is received from table search section 330. For frame rewriting, Ethernet (R) frame 4 300 or VLAN-tagged Ethernet (R) frame 4500 is force-pelled with E o E—MAC header and VLAN ID specified by table search unit 330 There are cases where the VLAN tag that stores the URL is stacked and rewritten to the MAC frame 4600 with VLAN tag E o E—.

Or there are other examples of encapsulation in the E o E—MAC header for Ethernet® frame 4300 or Ethernet tagged frame 4500 with VLAN tagging.

For the incoming frame, E o E—MAC header E o E—MAC—DA (destination address) is the broadcast address or multicast address, and E oE—MAC—SA (source address) is the local node's E o E — MAC address, E o E— MAC header is formed, and the E o E—MAC header is used to force the plunge, and the VLAN tag that stores the VLAN ID specified by the table search unit 330 is stacked. VLAN tagged E oE — MAC frame 4600 May be rewritten.

Or E o E— MAC frame 4400 or VLAN tag E o E— M For AC frame 4600, E o E— MAC header is decapsulated, VLAN tag is deleted, and Ethernet (R ) Frame 4300 or Ethernet (R) frame 4500 with VL AN tag may be rewritten.

After rewriting any of the above, or when rewriting is not necessary, the frame is transferred to the frame transfer unit 320 after receiving the frame from the frame analysis unit 300.

Regarding the main signal data frame, frame transfer section 320 transfers the main signal data frame received from frame rewriting section 310 to MACs 221 to 224 corresponding to the output ports received from table search section 330.

Regarding the control frame, the frame transfer unit 320 transfers the control frame received from the control frame distribution unit 370 to the MACs 221 to 224 corresponding to the output ports that simultaneously receive the control frame.

Based on the header information, frame type information, and input port information received from the frame analysis unit 300, the table search unit 330 refers to the forwarding table storage unit 340 to obtain output port information and frame rewrite information.

Hereinafter, processing according to the frame identification information of the table search unit 330 will be described.

(1) The frame type information is Ethernet (R) frame 4300 or VL

If the Ethernet (R) frame 4500 with AN tag is used and the input port is the user terminal side port, refer to MACZE 0 E-MAC table 342 in the forwarding table storage unit 340 (Fig. 4, see below) Then, E o E—MAC address for MAC-DA and the VLAN ID stored in the added VLAN tag are acquired.

(1-1) MAC / E o E— If the target entry exists in the MAC table 342, notify the frame rewrite unit 310 of the acquired EoE— MAC address and VLAN ID stored in the VLAN tag. E o E—Indicates MAC header power pseling and VLAN tag stacking. Also forwarding 2006/304420

22 Refers to the MAC table 300 of the table storage unit 340, and acquires the acquired EoE—MAC address and output port information for VLAN. If the target entry exists here, the output port information is notified to the frame transfer unit 320.

(1—2) MAC / E o E— If there is no target entry 1 in the MAC table 342, E oE—MAC—DA = broadcast or multicast, E oE—MAC—SA = g Node E oE—Indicates E o E—MAC header encapsulation in MAC. Further, the broadcast table 343 of the forwarding table storage unit 340 is referred to, the broadcast transfer port information is acquired, and the port information excluding the input port is notified to the frame transfer unit 320.

(2) If the frame type information is E o E—MAC frame 4400 or VLAN tagged E o E—MAC frame 4600, and the input port is a network side port, the destination MAC address (E o E— The operation differs depending on whether the MAC (DA address) is its own node address or another node address.

(2-1) For other node addresses, refer to the MAC table 341 in the forwarding table storage unit 340 to obtain the destination MAC address (EoE—MAC—DA address) and the output port for VLAN.

(2-1-1) If the target entry exists here, the frame transfer unit 320 is notified of the output port information, and the frame rewrite unit 310 is notified of the absence of frame rewrite.

(2-1-2) On the other hand, if the target entry does not exist, refer to the broadcast table 343, acquire the broadcast transfer port information, and notify the frame transfer unit 320 of the port information excluding the input port. At the same time, it notifies the frame rewriting unit 310 of no frame rewriting.

(2-2) If the destination MAC address (EoE—MAC 1 DA address) is the local node address, refer to the MAC table 3 1 in the forwarding table storage 340, and output port for MAC—DA and VL AN To get.

(2-2-1) If the target entry exists here, the output port information is notified to the frame transfer unit 320 and EoE—M is sent to the frame rewrite unit 310. Instructs deletion of AC header.

(2-2-2-2) On the other hand, if the target entry does not exist, refer to the broadcast table 343, acquire the broadcast forwarding port information, and notify the frame forwarding unit 320 of the port information excluding the input port. At the same time, it instructs the frame rewriting unit 310 to delete the E o E—MAC header.

The forwarding table storage unit 340 includes various tables that store information for transferring frames. The table includes the MAC table 341 that resolves the output port from the MAC address and VL AN ID, and E / E from the MAC address — MAC / E o that resolves the VL AN ID stored in the VL AN tag to be added E—There is a MAC table 342 and a broadcast table 343 that resolves the broadcast output port from the VL AN ID.

FIG. 4 is a configuration example of the foraging table storage unit 340.

The forwarding table storage unit 340 includes a MAC table 341, a MACZ E oE-MAC table 342, a broadcast table 343, a table write control unit 344, and a table read control unit 345. Writing new data to each table is performed via the table write control unit 344, and reading data from each table is performed via the table read control unit 345.

The configurations of MAC table 341, MAC node E o E—MAC table 342, and broad cast table 343 are as shown in FIGS. 5, 6, and 7, respectively. MAC / E o E— For MAC table 342, MAC EoE—

It is divided into the one in which the VL AN field is deleted from the MAC table 342 and the E o E—MAC / V LAN management table 1000 that resolves the corresponding VLAN from the E o E—MAC address shown in Figure 10. It may be configured.

In the following, description will be made with the integrated MACZE o E—MAC table 342 shown in FIG.

When MAC learning section 350 receives header information from frame analysis section 300, MAC learning section 350 refers to MAC table 341 in fording table storage section 340, and outputs the received header information to MAC_SA and VLAN. If the port is searched and there is no entry, MAC—SA is entered in the MAC address field, V VL AN is stored in the LAN field, and the receiving port is stored in the output port field. Here, if the receiving port is a network side port, the above learning function may be stopped.

When the header information is received from the frame analysis unit 300, the E o E—MAC learning unit 360 refers to the MACZE o E—MAC table 342 and refers to the MAC—SA of the received header information E o E— If the MAC is searched and there is no entry, MAC—SA is stored in the MAC address field, and E o E—MAC—SA is stored in the E o E-MAC address field.

The control frame distribution unit 370 transfers the control frame received from the frame analysis unit 300 to a predetermined processing unit, and transfers the control frame and output port information received from the processing unit to the frame transfer unit 320. In this configuration, since the processing unit is only the STP control unit 380, the control frame (hereinafter referred to as BPDU protocol data unit: BPDU) is transferred to the STP control unit 380 and the STP control unit. The BP DU and output port information received from 380 are transferred to the frame transfer unit 320.

The STP control unit 380 performs STPZRSTP port information update processing, etc. based on the BP DU received from the control frame distribution unit 370, recreates the BPDU, and transfers it to the adjacent switch. Transfer information to control frame sorter 370.

In the present invention, it is assumed that MSTP starts an RSTP tree for each VLAN ID, and the port information of the spanning tree based on RS TP is managed for each VLAN ID. The STP port information management table 800 shown in FIG. 8 is provided as a table for managing this information.

In the STP port information management table 800, STP tree information related to the switch port is managed for each VLAN ID. As port information of the STP tree, the role of the port and the port status are managed.

Ports are: Rot port (root port; shown as R in Fig. 8), Designated port (assigned port; shown as D in Fig. 8), A 1 ternate port (unassigned port; Fig. 8) Is described as A), and the port The states are the following: Forwarding state (denoted as in Fig. 8), L earning ng (learning) state (denoted as 1 in Fig. 8), D iscarding (stopped) state (denoted as d in Fig. 8) In the table, the port role is described as a set with the port status.

The S TP control unit 380 uses the VL in the S TP port state management table 800.

For each AN (ie for each STPZRSTP), the port role is the root port and the port state is the forward state (shown as RZ f in Fig. 8) or the port role is D esi gn ated The port whose port state is F or wa rding state or L earning state (shown as DZf or D / l in Fig. 8) is extracted, and the VL AN number and its port information are extracted from the table controller 39

Notify 0.

In addition, if there is a change in the RSTP tree configuration and there is a change in the port status, the contents of the STP port status management table 800 are updated and the port role is set to the root port and the port status. Is changed to a port or port role in the forwarding state, the port role is a signed port, and the port state is in the forwarding or L earning state, the new information is sent to the table control unit 390. Notice.

The table control unit 390 sets an output port for the E o E—MAC address based on the port information of the STP tree notified by the 380 STP control units (the MAC table 341 in the forwarding table storage unit 340). Update function).

In order to realize this processing, the table control unit 390 has a VLAN / EoE-MAC management table 900 shown in FIG.

VL ANZE o E— The MAC management table 900 is a VLAN ID that identifies each STP tree that is activated for each VLAN in the STP control unit 380 and the edge switch that is the root node of that STP tree. E o E— The MAC address is associated and managed. The contents of the VLAN / EoE-MAC management table 900 are set by the setting control unit 395.

Table control unit 390 has STP control unit 380 and VLAN number and corresponding to it 2006/304420

26 Port information ((A) Port role = R 0 ot port and port status = F or wa rding port, or (B) Port role = Designated port and port status = F or wa rding (A or B type and port number of the port that is in the state or L earning state), the following two types of rewrite processing are performed on the forwarding table storage unit 340.

The first rewriting process is performed by referring to the VLAN / E o E—MAC management table 900 to obtain the E o E—MAC address corresponding to the received VLAN and obtaining the MAC table 341 of the fording table storage unit 340. In Eo E— Rewrite the output port for the obtained MAC address and VLAN. The output port number to be rewritten is the port number of (A) received from the STP control unit 380.

In broadcast table 343, the output port for the acquired VLAN is rewritten. The output port number to be rewritten is the port number of (B) received from the STP control unit 380.

The second rewrite processing is performed for the obtained E oE MAC address in the MACZE o E—MAC table 342 of the forwarding table storage unit 340.

Rewrite VLAN ID. The VLAN ID to be rewritten is the VLAN ID notified from the STP control unit 380.

The setting control unit 395 receives the setting information input via the console IZO 260 in FIG. 2 via the CPU 250 and performs setting processing on an appropriate processing unit. Specifically, STP parameters and the like are set for the STP control unit 380. In addition, each value of the VLAN / E o E-MA C management table 900 of the table control unit 390 is set.

In the network shown in FIG. 1 composed of the edge switches E 1 to E 4 and the core switches C 1 and C 2 having the configuration described above, the frame transfer from the terminal T 3 to the terminal T 1 is taken as an example and the shortest path transfer of the present invention is performed. explain.

In FIG. 1, since the terminal T 1 is the destination terminal, the RS TP tree in which the edge switch E 1 connected to the terminal T 1 is the root node is the frame transfer path. The STP ID of this tree identifier is g 1, and this tree is identified by VLAN ID = g 1. In Figure 1, links that are active in the tree are bold. In this case, the STP port status management table 800 in each switch has the contents shown in Fig. 11 (Note that only the RSTP tree in which the edge switch E 1 is the root node is shown here. In fact, it also has information about the tree where the other node is the root node.)

According to FIG. 1, the frame from the terminal T 3 to the terminal T 1 is transferred via the edge switch E 3, the core switch C l, and the edge switch E 1. The table contents and table setting procedure in each switch for doing this will be explained.

The contents of each table of edge switch E3 are summarized in FIG. In edge switch E3, the STP port state management table 1 in the STP controller 380

(This is a table of the edge switch E3 of the STP port state management table 800 in FIG. 11 described above). The table control unit 390 has a VLANZEoE-MAC management table 1202.

In Fig. 1, since the RS TP tree in which E o E—the edge switch E 1 to which the MAC address e 1 is set is the root node is set as STP ID = g 1, the setting control unit 395 is used. In the VLAN / E oE—MAC management table 1202, the EoE—MAC address for VLAN ID = g 1 is set as e 1.

3? When the port state of the STP tree is stabilized, the control unit 380 refers to the STP port state management table 1201, and determines that the port role = Root port and the port state = Forwarding state port. VLAN ID = g 1 and port = p 1 are notified to the table control unit 390. Also, VLAN ID = g l and port = 3 are notified to the table control unit 390 as a port in which port role == D e s i g n a t e d port and port state = F o r w a r d i n g state or L a r n i n g state. ,

The table control unit 390 refers to the VL ANZE o E—MAC management table 1202 and obtains the MAC address = e 1 for the notified VLAN ID = g 1.

Based on this information, the table control unit 390 uses the forwarding table storage unit.

340 MAC table 341, MAC address = el, VLAN ID 2006/304420

28

Set the output port for = g 1 to the port p 1 reported from the STP controller 380. Also, in the broadcast table 343, the output port for VLAN ID = gl is set to the port p3 notified from the STP control unit 380. The resulting MAC table 341 has the contents shown in MAC table 120 3 in FIG. 12 (where the MAC learning unit 350 normally outputs the output port for MAC address t 3 when receiving a frame from user terminal T 3. Set by MAC address processing). Also, the broadcast table 343 has the contents shown in the broadcast table 1205 in FIG.

In addition, the table control unit 390 assigns the VLAN to the STP for the entry for which E o E—MAC address = e 1 in the MAC / E o E—MAC table 342 of the forwarding table storage unit 340. Set VLAN ID = g 1 notified from the control unit 380. The resulting MACZE o E—MAC table 342 has the contents shown in MACZE o E—MAC table 1204 in FIG.

Next, the table of the core switch C 1 that is the node of the next hop of the edge switch E 3 on the transfer path will be described. Figure 13 shows the contents of each table. The core switch C 1 has an S TP port state management table 1301 in the S TP control unit 380 (this is an excerpt from FIG. 11). The table control unit 390 has a VLAN / EoE-MAC management table 1302.

Similarly to the edge switch E 3, the VLAN / E o E—MAC management table 130 2 has the EoE—MAC address for VLAN I Dg 1 set to e 1 via the setting control unit 395. -In the STP control unit 380, when the port status of the STP tree is stable, refer to the STP port status management table 1 301, port role = Ro 0 t port and port status = F or wa rding status. As a certain port, the VLAN ID = g 1 and the port = p 1 are notified to the table control unit 390. In addition, VLAN ID = .gl, port = p 2 and p 3 are set as ports with port role = D esi gn ate port and port state = F or wa rding state or L earning state. Notify the table control unit 390.

The table control unit 390 refers to the VL AN / E o E_MAC management table 1302 and acquires EoE—MAC address = e 1 for the notified VLAN ID = g 1.

Based on this information, the table control unit 390 determines the forwarding table storage unit 3

In 40 MAC tables 341, the output port corresponding to MAC address = el and VLAN ID = g1 is set to port p1 notified from the STP control unit 380. Also, in the broadcast table 343, output ports for VLAN ID = gl are set to ports p 2 and p 3 notified from the STP control unit 380.

The resulting MAC table 341 becomes the MAC table 1303 in FIG. 13, and the broadcast table 343 has the contents shown in the broadcast table 1305.

Since core switch C 1 does not have MAC / E o E—MAC table 342, each table of core switch C 1 is the above.

Next, the table of the edge switch E1, which is the next hop node of the core switch C1 on the transfer path, will be described. Figure 14 shows the contents of each table. In the edge switch E 1, the STP control unit 380 has an STP port state management table 140 1 (see FIG. 11). Further, the table control unit 390 has a VL ANZE o E-MAC management table 1402. As with edge switch E3, VL ANZE o E—MAC management table 1402 has E o E—MAC address for VLAN ID = g 1 set to e 1 via configuration controller 395. Yes.

When the port state of the STP tree is stabilized, the STP control unit 380 refers to the STP port state management table 1401 and refers to a port whose port role is “Root port” and port state is “Forwarding” state. To be notified. In the current state, the relevant port does not exist, so notification is not performed.

In other words, edge switch E1 is an egress edge switch for this transfer, so there is no need to set the next hop output port. Also, port role = D es Notify the table controller 390 of VLAN ID = gl and ports = p 2 and p 3 as ports in the ignated port and port state-F or wa rding state or L earning state.

In the edge switch E 1, for the frame addressed to the end * T 1, the table search unit 330 selects Ε ο Ε— MAC header deletion processing as described in FIG. 3, and then the MAC table in FIG. Reference is made to 1403.

In the MAC table 1403, the output port for the MAC address t1 is set by the MAC learning unit 350 by normal MAC address processing when a frame is received from the user terminal T1.

In the broadcast table 343, the output ports for VLAN ID = g.l are set to the points p 2 and p 3 notified from the STP control unit 380. The resulting broadcast table 343 is broadcast table 1 405. Also, edge switch E 1 does not have an entry for transfer from user terminal T 3 to user terminal T 1 for MAC / E o E—MAC table 1 404 (it has entries for other transfers). (This is omitted in Figure 14).

The frame in each switch when the table setting described above is performed.

—The transfer process is described below using the node configuration diagram of FIG. 3 and the tables of FIGS.

The edge switch E3, which receives the Ethernet (R) frame 1500 addressed to the user terminal T1 from the user terminal T3 shown in Fig. 15 (see Fig. 1), receives a normal Ethernet (input frame) in the frame analysis unit 300. R) Analyzing that the frame is 4300, notifying header information, frame type information, and input port information to table search unit 330, and notifying frame rewriting unit 310 of the entire frame or payload portion.

The table search unit 330 refers to the MAC / EoE—MAC table 1204 (see FIG. 12) and stores it in the VL AN tag that stacks with EoE—MAC address = e 1 for the destination MAC address t 1 Acquire ID = g 1 and send EoE—MAC force pushing processing and VL AN tag to frame rewriting unit 310 6304420

Directs stack processing of 31.

Further, referring to MAC table 1203 (see FIG. 12), EoE—MAC address el, VLAN ID = g 1 and output port = port p 1 are obtained and notified to frame transfer section 320.

The frame rewriting unit 310 applies the E o E—MAC address = e 1 encapsulation processing and VLAN ID specified by the table search unit 330 to the frame or payload received from the frame analysis unit 300. = g Stack the VLA N tag with 1 stored. As a result, the output frame is an EoE frame 1600 shown in FIG.

When the frame rewriting unit 310 transfers the EoE frame 1600 to the frame transfer unit 320, the frame transfer unit 320 sends an EoE frame 1600 to the output port = port p 1 received from the table search unit 330. Is output.

In addition to the frame transfer process described here, the learning process is also performed.

The frame analysis unit 300 notifies the frame rewriting unit 310 and the table search unit 330 of information, and notifies the MAC learning unit 350 of header information, frame type information, and input port information.

The MAC learning unit 350 that has received the information refers to the MAC table 1203 and searches for the reception port for the MAC—SA = t 3 and VLAN ID = 0 in the received header information. If there is no entry, In the MAC address field

MAC—SA = t3, VLAN ID = 0 in the VLAN field, and receiving port p2 in the output port field.

Next, the core switch C 1 of the next hop after the edge switch E 3 will be described. The core switch C 1 that has received the E o E frame 1600 from the edge switch E 3 receives the E oE_

The MAC frame 4600 is analyzed, the header information, the frame type information, and the input port information are notified to the table search unit 330, and the entire frame or the payload portion is notified to the frame rewriting unit 310.

The table search unit 330 refers to the MAC table 13.03, 4420

32 Get output port = port p 1 for address e 1 and VL AN ID = 1, notify frame rewrite unit 310 of no frame rewrite, and output port p 1 to frame transfer unit 320 To be notified.

The frame rewriting unit 310 transmits the EoE frame 1600 received from the frame analysis unit 300 to the frame transfer unit 320 without performing the rewriting process. The frame transfer unit 320 outputs an E o E frame 1600 to the output port = port p 1 received from the table search unit 330.

In the learning process, the frame analysis unit 300 notifies the MAC learning unit 350 of header information, frame type information, and input port information, and the MAC learning unit 350 that has received the information refers to the MAC table 1303. If the MAC address of the received header information — S A- e 3 and VLAN ID = g 1 is searched and the entry does not exist, MAC 1 SA = e 3 in the MAC address field and the VLAN field Store g 1 in, and receive port P 2 in the output port field.

Note that this processing is not performed if the learning function is set to OFF when input port = network side port.

Next, the edge switch E 1 of the next hop of the core switch C 1 will be described. The edge switch E 1 that received the E o E frame 1600 from the core switch C 1 analyzes that the input frame is the E o E—MAC frame 4600 with a VL AN tag in the frame analysis unit 300, and includes header information and frame type. Information and input point information are notified to the table search unit 330, and the entire frame or pay-off portion is notified to the frame rewriting unit 310.

Since the destination MAC address (E o E—MAC—DA ′) is its own node, the table search unit 330 sends an E o E—MAC decapsulation process (deletion process) to the frame rewriting unit 320. ) And VL AN tag deletion processing, and refer to MAC table 1403 to obtain output port == port P 1 for MAC—DA = t 1 and VLAN ID = 0, and notify frame transfer unit 320 To do.

The frame rewriting unit 3 10 responds to the frame or payload received from the frame analysis unit 300 with respect to E o E—MA specified by the table search unit 330. Delete C address and VLAN.

As a result, the output frame is the Ethernet (R) frame 1 500 0 in FIG.

When the frame rewriting unit 3 10 transfers the Ethernet (R) frame 1 500 to the frame transfer unit 320, the frame transfer unit 320 transmits Ethernet to the output port = port p 1 received from the table search unit 330. (R) Frame 15000 is output. In parallel with the frame transfer process described here, the learning process is also performed.

Frame analysis unit 300 notifies header information, frame type information, and input port information to MAC learning unit 350 and EoE-MAC routing unit 360. The MAC learning unit 350 that received the information refers to the MAC table 1403 and searches for an output port for the MAC—SA = e 3 and VLAN ID = gl in the received header information. If there is no entry, the MAC learning unit 350 Store MAC—SA = e 3 in the address field, VL AN ID = g 1 in the VL AN field, and receive port P 2 in the output port field.

On the other hand, the E o E—MAC learning unit 360 that received the information refers to the MAC / EoE — MAC table 1404, searches for the EoE—MAC for the MAC—SA = t 3 in the received header information, and has an entry. Otherwise, MAC—SA = t 3 is stored in the MAC address field, and E o E—MAC—SA = e 3 is stored in the E o E—MAC address field. As a result, the MACZEoE—MAC table 1404 becomes the MAC / EoE—MAC table 1406.

When the edge switch E 1 outputs the Ethernet (R) frame 1 500 to the port p 1, the Ethernet (R) frame 1500 arrives at the user terminal T 1.

As described above, the one-frame (R) frame 1 500 sent from the user terminal T 3 to the user terminal T 1 passes through the edge switch E 3, the core switch C l, and the edge switch E 1. The destination user terminal T1 can be reached by the shortest route. According to the node configuration, table creation method, and data transfer method described above, the terminal

For the transfer from T 3 to terminal T 1, as shown in MAC table 1203 in FIG. 12 and MAC table 1303 in FIG. 13 at edge switch E 3 and core switch C 1, E o E—MAC address The output port for e 1 is set on the root port side of the tree with the edge switch E 1 as the root node, and it can be transferred to the Eg ress edge switch E 1 to which the terminal T 1 is connected via the shortest path. Is possible.

(Effects of the first embodiment)

Similar to the tree in which the edge switch E 1 described in this embodiment is a root node, a tree in which all edge switches are root nodes is generated, and the processing described in this embodiment is performed. By performing each node, the shortest path is formed between all the ED switches, and the Ethernet (R) frame 1500 can be transferred between all user terminals by the shortest path.

(Second embodiment)

In the first embodiment of the present invention, in order to perform optimum path forwarding in the EoE technology, a VL AN ID for identifying each RS TP tree and an edge serving as a root node of the RS TP tree Each node holds the correspondence with switches E1 to E4. Further, in the first embodiment, this association is set by an administrator via a server or the like via an external IF. On the other hand, in the second embodiment, each node automatically acquires the above correspondence.

The outline of the association processing procedure between the EoE-MAC address and VLAN ID for automatically acquiring the correspondence in the present embodiment is as shown in the flowchart of FIG.

EoE—Obtains MAC address and VLAN ID by receiving B PDU on spanning tree with edge node as root node (Step C 1) ₀

Step C—EoE acquired in step 1—Corresponding MAC address and VLAN ID Then, create a correspondence table (Step C 1-2).

Note that the outline of the frame transfer procedure and the forwarding table update procedure in the present embodiment is the same as the frame transfer procedure and the forwarding table update procedure in the first embodiment, and thus description thereof is omitted.

The detailed contents of the above association processing procedure will be clarified in the following description of each component and its operation.

Figure 17 shows the node configuration for automatic acquisition of correspondences by the association process.

FIG. 17 shows that the STP control unit 380 and the table control unit 390 are different from the node configuration shown in FIG. 3 in the first embodiment in that the STP control unit 1 780 and the table control unit.

The other parts are the same as those in Fig. 3 (the parts are indicated by the same names and symbols).

Hereinafter, the STP control unit 1780 and the table control unit 1790, which are the differences from the first embodiment, will be described.

In this embodiment, the correspondence between the VLAN ID that identifies the RSTP tree and the EoE-MAC address of the edge switch that is the root node of the RSTP tree is indicated by the transmission / reception process of the BP DU that is the control frame of STP. The information is automatically obtained from

First, the STP control unit 1780 will be described.

The STP control unit 380 of the first embodiment receives the BPDU transferred from the control frame distribution unit 370, updates the STP port state based on the information of the BPDU, and performs the STP port state management table 1 In addition to updating 100, a new B PDU was created, and a new BPDU was transferred to the control frame distribution unit 370 to transfer the B PDU to the next hop node. In addition, the table controller 390 is notified of the port number that matches the condition of each port and the VLAN ID that is the identifier of the STP tree.

In contrast, the STP control unit 1780 of the present embodiment has a new function of copying the BP DU received from the control frame distribution unit 370 and transferring the copied BP DU to the table control unit 1 790. Have. BPDU processing and new B The STP control unit 380 has functions such as PDU creation.

Next, the table control unit 1790 will be described.

When receiving the VL AN and the port number from the STP control unit 380, the table control unit 390 of the first embodiment refers to the VLAN / E o E—MAC management table 900 and notifies the notified VL AN. The EoE—MAC address corresponding to the EoE—MAC address is acquired, and the received port number is set as the output port for the acquired EoE—MAC, VLAN in the MAC table 341 in the forwarding table storage unit 340. . Also, for the MAC / E o E—MAC table 342, the received VLAN ID is set for the entry related to the acquired E oE—MAC address.

Here, the VLAN / EoE—MAC management table 900 is supposed to be set by the setting control unit 395, but in this embodiment, the setting of the VLANZE oE—MAC management table 900 is not performed from the outside. This is done at the Bull Control 1790.

When the table control unit 1790 receives B P D U from the three-unit control unit 1780,

Information to be held in the VLAN / EoE-MAC management table 900 is acquired from information stored in the BPDU.

FIG. 18 is a format diagram of the BPDU.

BPDU 1800 includes MAC-one DA field 1801, MAC-SA field 1802, VLAN tag field 1803, Type field 1804,

BPDU parameter area 1 805 and FCS field 1806 are configured. B PDU parameter area 1 805 is the Protocol—I dentifier field J Red 181 1, Protocol_V ersi on—I denfi e'r field 1812 , BPD U— Type field 181 3, Flags field 1814, Rot— I dentifier field 1 81 5, Rot—

P ath— Cost field 18 16, Bridge 1 I dentifier field 18 17, Port — I dentifier field 1818, Message— A e field 1819, Max 1 A ge field 1820, He 1 1 o— T i me field 1 821, Fo rwa rding one D e 1 ey 2006/304420

37 Field 1822.

The MAC—DA field 1801 stores the destination MAC address. The MAC_SA field 1802 stores the source MAC address.

The VLAN tag field 1803 stores VLAN ID as an identifier for identifying the spanning tree. The Type field 1804 stores the frame type identifier.

In the B PDU parameter area 1805, various parameters of the B PDU described in I EEE802.1D or I EEE802.lw are stored. Each parameter field of the BPDU parameter overnight field 1805 stores the corresponding parameter value described in I EEE802.1D or I EEE802.lw.

The FCS field 1806 stores a frame check sequence. Figure 19 shows the configuration of the Root — Identifier field 1815 in the BPDU parameter area 1805.

The Root—Id nt fi ier field 18 15 is composed of the Pri ri yt field 18151, the fixed value field 18142, and the MAC—Ad rd s s s field 18143.

MAC—Ad rd s s field 18143 stores the MAC address of the root node. Rot—I dentifier field 181 5 is 8 bits long, Priority field 1 8 141 is 4 bits long, fixed value field 18142 is 12 bits long, MAC—Address field 1 8143 is 6 bytes long It is.

Therefore, by extracting the lower 6 bytes of the Root—Id nt i fi er field 1815, the MAC address of the root node of that spanning tree can be obtained.

As described above, as shown in the BPDU configuration in Figs. 18 and 19, the RSTP tree is identified by the information in the VLAN tag field 1803 of the BPDU and the MAC—Address field 18143 in the Rot—I dentifier field 1815. VLAN ID that is the identifier of the RSTP tree root node 04420

38

As described above, when the table control unit 1790 receives a BPDU from the STP control unit 1780, the information stored in the VLAN tag field 1803 of the BPDU and the MAC—Address field in the Route—I dentifier field 1 81 5 18 Store the information stored in 143 in the VLAN field and EoE—MAC address field of VLAN / E o E—MAC management table 900, respectively. After obtaining the information, the BPDU is discarded. The VLAN / E o E—MAC management table 900 is set by performing such processing each time a B PDU is received. Also, instead of processing each time a BPDU is received, a list of processed VLANs is managed in each VLAN, and an association acquisition process is performed for an unprocessed VLAN when a BPDU is received. You can do it.

Note that the function of setting information in the forwarding table storage unit 340 using information in the VL ANZE o E-MAC management table 900 is the same as that of the table processing unit 390.

In the example explained above, 3? The control unit 1780 copies the BPDU and transfers it to the table control unit 1790. The table control unit 1790 obtains the association between the VLAN and the root node E o E-MAC address from the received BPDU. It is also possible to change the function sharing.

For example, when the STP control unit 1780 receives the BPDU, it performs the association acquisition process performed by the table control unit 1790 in the above description, and notifies the table control unit 1 790 of the E o E-MAC address corresponding to the VLAN ID. The table control unit 1790 can also write each received information to the VLAN / E o E—MAC management table 900.

Information in the VLA N / EoE_MAC management table 900 can be automatically set by the STP control unit 1780 and the table control unit 1790 described above.

Using the information in the VLAN / E o E-MAC management table 900 set in this way to set each table in the forwarding table storage unit 340 and transferring main signal data along the optimum route, This can be realized by the operation of each unit described in the first embodiment. (Effect of the second embodiment)

As described above, according to the node configuration, the table creation method, and the data transfer method in the second embodiment, it is possible to transfer the transfer between each terminal through the shortest path, and further, the necessary STP tree. It is possible to automatically set the correspondence between the VLAN ID and the root node's EoE—MAC address to identify the MAC address.

(Third embodiment)

In the third embodiment, the VLAN ID for identifying the STP tree and the EoE—MAC address of the root node are associated with each other by a method different from the second embodiment (BPDU transmission / reception processing). Set automatically.

The outline of the association processing procedure between the E o E-MAC address and the VLAN ID in each switch of the present embodiment is as shown in the flowchart of FIG. Receive a data frame (step D—1).

Step D—Calculate VR AN ID from the E o E—MAC address of the data frame received in Step 1 (Step D—2).

Create a correspondence table by associating the VLAN ID calculated in Step D—2 with the E o E—M AC address (Step D—3).

In addition, the node (switch) to which the source terminal is connected has a procedure for storing the VLAN ID in an arbitrary 12-bit area in the E o E-MAC address 48 bits in the received frame. . In the following, VLAN I is assigned to the lower 1 2 bits.

An example of storing D will be described.

Note that the outline of the frame transfer procedure and the forwarding table update procedure in the present embodiment is the same as the frame transfer procedure and the forwarding table update procedure in the first embodiment, and thus the description thereof is omitted.

FIG. 20 shows a node configuration in the present embodiment.

FIG. 20 shows that the table control unit 390 is changed to the table control unit 2090 with respect to the node configuration shown in FIG. 3 in the first embodiment, and the frame analysis unit 300 has been changed to the frame analysis unit 2300, and the other parts are the same as those in Fig. 3 (each part is indicated by the same name and symbol). In the following, the table control unit 2090 and the frame analysis unit 2300, which are the differences from the first embodiment, will be described.

R In this embodiment, E o E— MAC address is set to automatically obtain the association between the VLAN ID that identifies the STP tree and the E o E—MAC address of the edge switch that is the root node of the RSTP tree. In this case, the E o E—MAC address is associated with the VLAN ID so that the VLAN ID can be automatically obtained from the E o E—MAC address.

First, EoE— MAC address setting is explained.

E o E—The MAC address consists of 48 bits, the same as a normal MAC address. Here, as a method for setting the EoE—MAC address, a setting is made so that EoE—MAC address can be calculated by performing some operation on VLAN ID. In this embodiment, as an example, as shown in FIG. 21, the VLAN ID is stored in the lower 12 bits of the 48 bits of the E o E-MA C address, and the upper 36 bits are fixed values. It shall be.

The stored VLAN ID is V L A N I D which is the identifier of R S T P L1 whose edge switch is the edge switch to which the E o E—MAC address is assigned.

Next, the frame analysis unit 2300 will be described. In addition to the operation of the frame analysis unit 300, the frame analysis unit 2300 also transfers the overnight frame to be transferred to the frame analysis unit 310 to the table control unit 2090. Other operations are the same as those of the frame analysis unit 300.

Next, the table control unit 2090 will be described. When receiving the VLAN and the port number from the STP control unit 380, the table control unit 390 of the first embodiment refers to the VL ANZE o E—MAC management table 900, and EoE corresponding to the notified VLAN— The MAC address is acquired, and the received port number is set as the output port for the acquired E o E-MAC and VLAN in the MAC table 341 in the forwarding table storage unit 340. MA C / E o E—Sets the received VLAN ID for the entry related to the acquired E o E—MAC address in the MAC table 342.

On the other hand, in this embodiment, VLAN ID is calculated from the EoE—MAC address of the overnight frame, and the VL AN / E o E—MAC management table 900 is created.

When the spanning tree port state is changed, the table control unit 2090 receives the VLAN ID and port information related to the changed spanning tree from the STP control unit 380. Further, when the table control unit 2090 receives the data frame from the frame analysis unit 2300, the table control unit 2090 calculates the corresponding VLAN ID from the E o E-MAC address of the data frame.

In this embodiment, predetermined 12 bits (lower 12 bits in this example) are extracted as VLAN ID from the 48-bit E o E—MAC address of the received data frame. As a result, the correspondence between E o E—MAC address and VLAN ID can be acquired, and both are stored in the VLANZE 0 E—MAC management table 900.

The function for setting the forwarding table storage unit 340 based on the acquired correspondence is the same as that of the table processing unit 390.

The VLAN ID corresponding to the E o E—MAC address can be acquired by the EoE—MAC address setting and table control unit 2090 described above, and each table of the forwarding table storage unit 340 is set. The transfer of the main signal data along the optimum path can be realized by the operation of each unit described in the first embodiment.

In the above description, the VLAN ID is calculated from the EoE—MAC address of the received data frame, and the VL AN / E o E—MAC management table 900 is created. However, based on the received BPDU frame, VLANZEoE— It is also possible to create the MAC management table 900.

(Effect of the third embodiment)

As described above, the node configuration, the table creation method, and the data in the third embodiment 6304420

42 According to the evening transfer method, it is possible to transfer between each terminal with the shortest route, and further, the VL AN ID for identifying the STP tree required for that purpose and the root node's E oE — It is possible to automatically set MAC address mapping. (Fourth embodiment)

In the fourth embodiment of the present invention, each edge switch creates an STP / RSTP tree with its own node as a root node in order to realize optimal path forwarding in the EoE technology. Each switch in the switch holds a correspondence between the VLAN ID that identifies each STPZR STP tree and the E o E-MAC address of the edge switch that is the root node of the STPZR STP tree. The EoE technology of the Eg ress edge switch corresponding to the destination MAC address of the user terminal in EoE technology uses a learning mechanism for resolving the MAC address, and the VLAN for identifying the above RS TP tree. Refer to the correspondence between ID and E o E—MAC address, and set the output port for E o E—MAC address.

The outline of the forwarding table update procedure in this embodiment is as shown in the flowchart of FIG.

For each unknown frame, each switch transmits a learning frame on the same level as the root node (switch) (Step E-1).

When a learning frame is received, the output port corresponding to the acquired EoE—MAC address is set as the root port, and the forwarding table is updated (step E-2).

Based on the VLAN ID (Spanning Tree Protocol ID) and changed port information (described later), a change in the STP port status (described later) is received (step B-1).

Referring to the correspondence table, Eo corresponding to VLAN ID in Step B—1

E—Obtain a MAC address (Step B—2).

Update the forwarding table by rewriting the output port corresponding to the E o E— MAC address obtained in Step B—2 to the notification port from the Spanning Tree Protocol (Step B-3). Note that the outline of the frame transfer procedure in the present embodiment is the same as the frame transfer procedure in the first embodiment, and the association process is unnecessary, and thus the description thereof is omitted.

The detailed contents of the above-mentioned forwarding table update procedure will be clarified in the following explanation of each component and its operation.

The node configuration in this embodiment is shown in FIG.

FIG. 22 is different from the node configuration shown in FIG. 3 in the first embodiment in that the STP control unit 380 and the table control unit 390 are changed to the STP control unit 2280 and the table control unit 2290. These parts are the same as in Fig. 3. Hereinafter, the STP control unit 2280 and the table control unit 2290 that are differences from the first embodiment will be described.

First, the STP control unit 2280 will be described.

The STP control unit 380 of the first embodiment receives the BP DU transferred from the control frame distribution unit 370, updates the STP port state based on the information of the BP DU, and sets the STP port state. The management table 1 100 was updated, a new B PDU was created, and a new BPDU was transferred to the control frame distribution unit 370 to transfer the B PDU to the next hop node. In addition, the port control unit 390 is notified of the port number that matches the condition of the port status and the VLAN ID that is the identifier of the STP tree in each port.

On the other hand, in the STP control unit 2280 of the present embodiment, the port status condition notified to the table control unit 390 in the above processing is a port that is not in the discarding state regardless of the port role. The port number that matches the conditions and the VLAN ID that is the identifier of the STP tree are notified.

Next, the table control unit 2290 will be described.

In the table control unit 390 according to the first embodiment, the V S L from the STP control unit 380

When the AN and port number are received, the EoE MAC address corresponding to the VLAN notified from VLAN / E o E—MAC management table 900 is obtained, and the MAC table in the forwarding table storage unit 340 is obtained. For 341, the acquired E o E— MAC address, port received as output port for VLAN Set the port number received as the broadcast output port for the acquired VL AN for the broadcast table 343, and MAC E o E— For the M'AC table 342, the acquired E o E— A VLAN ID was set for the entry related to the MAC address.

In contrast, in the table control unit 2290 of the present embodiment, VLAN / E o

E— Does not have the MAC management table 900, and only performs the process of setting the output port corresponding to the acquired VL AN ID for the broadcast table 343 in the forwarding table storage unit 340 in the above process. .

In the present embodiment, optimal path forwarding is performed by a node having such a configuration by the method described below. Since the table setting method at each node is different from that of the first embodiment, the table contents and table setting at each node will be described below.

The premised network is the network of FIG. 1 similar to the first embodiment, and the shortest path transfer of the present embodiment will be described by taking the frame transfer between the terminal T 1 and the terminal T 3 as an example.

In this embodiment, the learning mechanism for resolving the E o E— MAC address of the Eg ress edge switch corresponding to the destination MAC address of the user terminal is used, and the VL AN ID and E o E— MAC address The learning mechanism is explained to set the output port for Eo E-MAC address with reference to the mapping of.

The following explanation will be made using the node configuration diagram of FIG. 22 and the table diagrams of FIGS.

For the sake of explanation suitable for FIG. 1, it is assumed that the frame transfer from the user terminal T 3 to the user terminal T 1 is performed after the frame transfer from the user terminal T 1 to the user terminal T 3. To do.

The edge switch E 1 holds the MAC table 2301, the MAC / E o E—MAC table 2302, and the broadcast table 2303 shown in FIG. Here, in this embodiment, the MAC Έ o E—MAC table 2302 has an F 1 ag field in addition to the configuration so far, and a broadcast frame when not learning is performed. It is assumed that the transmission of frames is controlled (the same applies to MAC / E o E—MAC table 2502 of edge switch E 3 in FIG. 25).

When the edge switch E 1 receives the Ethernet (R) frame 2600 of FIG. 26 as a frame addressed to the user terminal T 3 from the user terminal T 1 at the port p 1, the frame analysis unit 300 receives the input frame as a normal Ethernet (R ) Analyzes that the frame is 4300, notifies header information, frame type information, and input port information to the table search unit 330, and notifies the frame rewriting unit 310 of the entire frame or payload portion.

Since the table search unit 330 refers to the MAC / E oE—MAC table 2302 and there is no entry for the destination MAC address t 3, the frame search unit 330 sends an E o E—MAC—DA = broadcast to the frame rewrite unit 310. Or Multicast, E o E— MAC— S Local node E o E— MAC E o E— MAC header encapsulation is instructed, and MAC / E o E— MAC table 2302 MAC address field t 3 , Set the F 1 ag field to 1.

In addition, since the VLAN ID of the RS TP tree in which the local node is the root node is g 1, the frame rewriting unit 310 is also instructed to stack VLAN ID = g 1.

Also, refer to the Procast Table 2303, obtain the ports p 2 and p 3 as the broadcast forwarding port information for VLAN I D-gl, and forward frames p 2 and p 3 excluding the input port Part 320 is notified.

The frame rewriting unit 3 10 receives the EoE broadcast frame 2700 shown in Fig. 27, which is a frame in which the VLAN tag storing the VLAN ID is stacked according to the instruction from the table search unit 330. The frame transfer unit 320 outputs the EoE broadcast frame 2700 to the output ports p 2 and p 3 received from the table search unit 330.

In the learning process, the frame analysis unit 300 notifies the frame rewriting unit 310 and the table search unit 330 of information, and notifies the MAC learning unit 350 of header information, frame type information, and input port information. The MAC learning unit 350 that has received the information refers to the MAC table 2301 and searches for the reception port for the MAC—SA = t 1 and VLAN ID = 0 in the received header information. If there is no entry, MAC—SA = tl in the MAC address field, VLAN ID = 0 in the VLAN field, and receiving port p 1 in the output port field. In the first embodiment, the MAC

—The learning unit 350 can be configured to stop the MAC learning process when the receiving port is a network side port. However, in the fourth embodiment, the MAC learning process is performed regardless of the receiving port.

Next, the core switch C 1 of the next hop after the edge switch E 5 will be described. The core switch C 1 holds the MAC table 2401 and the professional cast table 2403 shown in FIG.

Core switch C 1 that has received EoE broadcast frame 2700 from edge switch E 1 analyzes that the input frame is an E oE-MAC frame 4600 with a VLAN tag in frame analysis unit 300, and includes header information and frame type information. The input port information is notified to the table search unit 330, and the entire frame or the payload portion is notified to the frame rewriting unit 310.

Since the destination MAC address is a broadcast address, the table search unit 330 refers to the broadcast table 2403, obtains the broadcast transfer ports P 1, p 2, and p 3 for VLAN ID = g 1 and inputs the input points. Notify ports p 2 and p 3 except for to frame transfer unit 320. In addition, the frame rewriting unit 310 is notified of no frame rewriting.

The frame rewriting unit 310 transfers the E o E procast frame 2700 received from the frame analysis unit 300 to the frame transfer unit 3, 20 without performing the rewriting process.

The frame transfer unit 320 outputs an E o E broadcast 卜 frame 2700 to the output ports p 2 and p 3 received from the table search unit 330. In the learning process, the frame analysis unit 300 notifies the MAC learning unit 350 of header information, frame type information, and input port information, and the MAC learning unit 350 that has received the information refers to the MAC table 2401. Receive JP2006 / 304420

If there is no entry, MAC—SA = el in the MAC address field and VLAN ID = g 1 in the VLAN field are searched. The receiving port P1 is stored in the output port field.

Next, the edge switch E 3 of the next hop of the core switch C 1 will be described. The edge switch E 3 holds the MAC table 2501, the MACZEo E—MAC table 2502, and the broadcast 卜 table 2503 shown in FIG. Upon receiving the EoE broadcast frame 2700 from the core switch C 1, the edge switch E 3 analyzes in the frame analysis unit 300 that the input frame is the E o E—MAC frame 4600 with a VLAN tag, and includes header information and frame type. Information and input port information are notified to the table search unit 330, and the entire frame or payload portion is notified to the frame rewriting unit 310.

Since the destination MAC address is a broadcast 卜 address, the table search unit 330 refers to the broadcast table 2503, acquires the broadcast transfer ports p 1 and p 3 for VL AN ID = g 1, and removes the input port Point P 3 is notified to the frame transfer unit 320 and the frame rewriting unit 310 is instructed not to rewrite.

The table search unit 330 also instructs the frame rewriting unit 320 to perform EoE-MAC decapsulation processing (deletion processing) and VLAN tag deletion processing because the node is an edge switch. Referring to 2501, if it is found that there is no entry for MAC—DA = t 3 and VLAN ID = 0, refer to broadcast table 2503 and use port p 2 as the broadcast forwarding port information for VLAN ID = 0. And notifies the frame transfer unit 320.

The frame rewriting unit 3 10 transfers the frame or payload received from the frame analysis unit 300 to the frame transfer unit 320 without rewriting as instructed by the table search unit 330, and copies it. The other frame is deleted from the E o E—MAC address and VLAN tag specified by the table search unit 330 and output to the frame transfer unit 320. The result As a result, the output frame is the Ethernet (R) frame 2700 in FIG. The frame transfer unit 320 outputs an EoE broadcast frame 2700 to the output port p 3 received from the table search unit 330 and outputs an Ethernet (R) frame 2600 to the output port p 2. In parallel with the frame transfer process described here, the learning process is also performed.

The frame analysis unit 300 notifies the MAC learning unit 350 and the E o E—MAC routing unit 360 of header information, frame type information, and input port information.

The MAC learning unit 350 that has received the information refers to the MAC table 250 1 and searches for the reception port for the MAC—SA e 1 VL AN ID = .g 1 in the received header information. If there is no entry, Store MAC—SA = el in the MAC address field, VL AN ID = g 1 in the VL AN field, and receive port P 1 in the output port field.

On the other hand, the E o E—MAC learning unit 360 that has received the information refers to the MACZEoE one MAC table 2502, searches for the E o E—MAC for the MAC—SA = t 1 in the received header information, and the entry exists. If not, enter MAC—SA = t 1 in the MAC address field, E oE—MAC—SA = e 1 in the E oE—MAC address field, and VL AN ID = g 1 in the VL AN field. And set the F 1 ag field to 0.

Thereafter, the Ethernet (R) frame 2600 output from the edge switch E 3 arrives at the user terminal T 3.

Next, the case where the user terminal T 3 transfers a frame to the user terminal T 1 will be described.

At the edge switch E3, the port! 2) When the Ethernet (R) frame 1500 in FIG. 15 is received from the user terminal T 3 as a frame addressed to the user terminal T 1 in 2, the frame analysis unit 300 confirms that the input frame is a normal Ethernet (R) frame 4300. The header information, frame type information, and input port information are notified to the table search unit 330, and the entire frame or payload portion is notified to the frame rewriting unit 310. The table search unit 330 sends an E o E—MAC—DA-broadcast to the frame rewriting unit 310 because the F 1 ag field of the entry for the destination MAC address t 1 in the MACZE o E—MAC table 2502 is 0. Or Multicast, E o E—MAC—SA = Self-Node E o E—Indicates MAC o 3 E o E—MAC header encapsulation, MAC / E o E—MAC table 2

Set 1 in the F 1 a g field of the entry for the destination MAC address t 1 of 502. As a result, the MACZE o E—MAC table 2502 is updated with the MAC / E o E—MAC table 2505. Also, the local node becomes the root node; since the VLAN ID of the R STP tree is g 3, the stack of VL AN ID = g 3 is also instructed to the frame rewriting unit 310. Also, by referring to the broadcast table 2503, the broadcast transfer ports pl and p 3 for VLAN I = g 3 are obtained, and the ports p 1 and p 3 excluding the input port are notified to the frame transfer unit 320 (FIG. 25). In Fig. 1, the broadcast port for VLAN ID = g 3 is set from the RS TP single port whose root node is the edge switch E 3 (not shown in Fig. 1).

The frame rewriting unit 310, according to the instruction from the table search unit 330, forcibly uses the EoE MAC header and stacks the VLAN tag storing the VLAN ID, so that the transmission frame is the EoE broadcast frame shown in FIG.

2800.

The frame rewriting unit converts the EoE broadcast frame 2800 into the frame transfer unit.

The frame transfer unit 320 outputs the frame to the output ports p 1 and p 3 received from the table search unit 330.

A learning process is also performed in parallel with the frame transfer process described here. The frame analysis unit 300 notifies the MAC learning unit 350 of header information frame type information and input port information. The MAC learning unit 350 that received the information refers to the MAC table 2501 and searches for the receiving port for the received header information MA C — SA = t 3 and VLAN ID = 0. If there is no entry, MAC—SA = t 3 in the MAC address field, VLAN ID = 0 in the VLAN field, and receive port p 2 in the output port field To do. As a result, the MAC table 2501 becomes the MAC table 2504. Next, the core switch C1 of the next hop of the edge switch E3 will be described. The edge switch E 3 receives the E o E broadcast frame 2800 from the edge switch E 3, and the frame switch C 1 analyzes that the input frame is an E o E-MAC frame 4600 with a VLAN tag in the frame analysis unit 300. The header information, frame type information, and input port information are notified to the table search unit 330, and the entire frame or payload portion is notified to the frame rewriting unit 1010.

Since the destination MAC address is the broadcast address, the table search unit 330 refers to the broadcast table 2403, acquires the broadcast forwarding ports p 1, p 2, and p 3 for VLAN ID = g 3 and excludes the input ports. The frame points pl and p3 are notified to the frame transfer unit 320. Also, the frame rewriting unit 310 is notified of the absence of frame rewriting.

The frame rewriting unit 310 transfers the EO procast frame 2800 received from the frame analysis unit 300 to the frame transfer unit 320 without performing the rewriting process.

The frame transfer unit 320 outputs an EoE broadcast frame 2800 to the output ports p 1 and p 3 received from the table search unit 330. As the learning process, the frame analysis unit 300 notifies the MAC learning unit 350 of header information, frame type information, and input port information.

The MAC learning unit 350 that has received the information refers to the MAC table 240 1, searches for the reception point for the received header information MAC—SA = e 3 and VL AN ID = g 3, and there is no entry. In this case, MAC—SA = e 3 is stored in the MAC address field, VL AN ID = g 3 is stored in the VL AN field, and the receiving port P 2 is stored in the output port field. As a result, the MAC table 240 1 is updated to the MAC table 2404.

Next, the edge switch E 1 of the next hop of the core switch C 1 will be described. The edge switch E 3 that has received the E oE broadcast frame 2800 from the core switch C 1 analyzes in the frame analysis unit 300 that the input frame is the E o E—MAC frame 4600 with a VLAN tag, and includes header information, F 4420

51 Sends frame type information and input port information to the table search unit 330, and notifies the frame rewriting unit 310 of the entire frame or payout portion.

Since the destination MAC address is the broadcast address, the table search unit 330 refers to the broadcast table 2303, acquires the broadcast forwarding ports p 2 and p 3 for VLAN ID = g 3, and acquires the port P 3 excluding the input port. Notifying the frame transfer unit 320 and instructing the frame rewriting unit 310 not to rewrite.

In addition, since the node is an edge switch, the table search unit 330 instructs the frame rewriting unit 320 to perform EoE-MAC decapsulation processing (deletion processing) and VLAN tag deletion processing. Referring to Table 2301, obtain port pi as an output port for MAC—DA = tl, VLAN ID = 0, and notify frame transfer unit 320 of it.

The frame rewriting unit 310 transfers the frame or payload received from the frame analysis unit 300 to the frame transfer unit 320 without rewriting as instructed by the table search unit 330. E o E— Deletes the MAC address and VLAN tag for the copied frame, and outputs it to the frame transfer unit 320. As a result, the output frame is the Ethernet (R) frame 1500 in FIG.

The frame rewriting unit 310 transfers the Ethernet (R) frame 1 500 to the frame transfer unit 320.

The frame transfer unit 320 outputs an EoE broadcast frame 2600 to the output port 3 received from the table search unit 330, and outputs an Ethernet (R) frame 1500 to the output port p i.

A learning process is also performed in parallel with the frame transfer process described here. The frame analysis unit 300 notifies the MAC learning unit 350 and the E o E—MAC routing unit 360 of header information, frame type information, and input port information.

The MAC learning unit 350 that has received the information refers to the MAC table 2301 and corresponds to the MAC—SA = e 3 and VL AN ID = g 3 of the received header information. If the receiving port is searched and there is no entry, MAC 1 SA = e 3 in the MAC address field, VL AN ID = g 3 in the VL AN field, and receiving port p 2 in the output port field. Store. As a result, the MAC table 230 1 is updated to the MAC table 2304.

On the other hand, the E o E—MAC learning unit 360 that has received the information refers to the MAC / EoE one MAC table 2302, searches for the E o E—MAC for the MAC—SA = t 3 in the received header information, and If EoE—MAC address field does not exist, EoE—MAC—SA = e 3 is stored in the EoE—MAC address field, and V LAN ID = g 3 is stored in the V LAN field. As a result, MAC / E o E—MAC table 23 02 is updated to MACZE o E—MAC table 2305.

Thereafter, the Ethernet (R) frame 1 500 outputted from the edge switch E 1 arrives at the user terminal T 1.

(Effect of the fourth embodiment)

As described above, in the present embodiment, the E o E broadcast frame sent when the E o E—MAC address of the E gress edge switch corresponding to the destination MAC address of the user terminal is unknown By stacking VL AN tags that store the VLAN ID that is the identifier of the RS TP tree for which the ress edge switch is the root node, and sending them on that RSTP tree, each node in the network The frame is received at the root point of the RS TP tree. At this time, the learning mechanism is activated and the E o E— MAC address and Ingress edge switch of the In ng ress edge switch stored in the MAC—SA field is the root node of the RS TP tree VL AN ID As an egress port for the RSTP tree, the root port of the RSTP tree is learned and held in the MAC table. After that, frames are forwarded according to this MAC table, so the frames are forwarded in the direction of the root port of the R S TP tree whose root node is the E gres s edge switch. This makes it possible to transfer frames on the optimal route.

Note that in addition to the method of this embodiment, each EDGES switch has its own EoE— Frames with the MAC address MAC-SA may be sent periodically. In this case, it may be possible to quickly determine the output port for the EoE-MAC address. '(Fifth embodiment)

In the fifth embodiment, optimum route transfer in the E o E network when a VPN is assembled between user terminals in the first to fourth embodiments will be described.

Figure 29 shows the assumed network diagram.

Figure 29 shows a terminal connected to port p 1 of edge switch E 1 (only terminal T 1 in FIG. 29) and a terminal connected to port p 2 of edge switch E 3 in the network of FIG. 1 (FIG. 29). Terminal T 3 only) forms VP N # A. When VPN is built, the format of E o E frame is E o E frame 4600 with VL AN tag in Fig. 52, and VPN ID is stored in VLAN tag field 51 10 to identify VPN. In this case, the VPN ID is set so that the VLAN ID and VPN ID assigned for identification of the RS TP tree in the VLAN space do not overlap.

The outline of the frame transfer process table setting process procedure and the association process procedure in the present embodiment is the same as that of the first step except that the VP NID is added to the frame at the transfer source node and this VPN ID is deleted at the destination node. Since it is the same as each procedure in the first to fourth embodiments, the description is omitted.

The detailed contents of the above procedure will be clarified in the following explanation of each component and its operation.

FIG. 30 shows a node configuration in the present embodiment.

FIG. 30 shows that the frame rewriting unit 310 is the frame rewriting unit 3010, the table search unit 330 is the table search unit 3030, and the node configuration shown in FIG. 3 in the first embodiment. The singing table storage unit 340 has been changed to a forging table storage unit 3040, and other parts are the same as those in FIG.

The node configuration based on this embodiment is the same as that of the first embodiment. In addition to the node configuration (Fig. 3), the node configurations of the second to fourth embodiments (Fig. 17,

20 and 22) However, the forwarding process when considering VPN in this embodiment is common.

Therefore, the STP control unit 380 and the table control unit 390 in FIG. 30 may be the STP control unit 1780 and the table control unit 1790 in the second embodiment, or the STP control in the third embodiment. The unit 380 and the table control unit 2 090 may be used, or the STP control unit 2280 and the table control unit 2290 in the fourth embodiment may be used.

In the following, description will be made centering on the frame rewriting unit 3010, the tape search unit 3030, and the forwarding table storage unit 3040, which are the differences from the first embodiment.

Frame rewrite section 3010 rewrites the frame for the main signal data frame received from frame analysis section 300 when instructed by table search section 3030. Regarding frame rewriting, the difference from the processing in the frame rewriting unit 310 is as follows.

In frame rewriting unit 3 10, when the E o E- MAC header is encapsulated and the VLAN tag storing the VLAN ID is stacked, the frame rewriting unit 30 10 instructs the table search unit 3030 after the VLAN tag. Stack the VL AN tag that stores the specified VP NID. That is, stack two VLAN tags.

The format of E o E frame 3600 with V LAN tag after this processing is illustrated.

Shown in 36.

¥ 18> 1 Tag 1 field stores the identifier of the RS TP tree, VLAN—ID, and VLAN tag 2 field stores the VPN ID. In addition, when deleting the header, the frame rewriting unit 3010 performs header deletion processing for the frame 3600. Therefore, both the VLAN tag 1 and the VLAN tag 2 are added to the EoE—MAC header decapsulation. delete.

As shown in FIG. 31, the forwarding table storage unit 3040 provides a V ID for resolving the VPN ID with respect to the forwarding table storage unit 340 of FIG. A PN management table 3046 is added.

If the VPN setting is port-based, the VPN management table 3046 holds the port ZVPN table 30461 that manages the VPN ID for the port, as shown in Figure 32, and the port for the VPN ID shown in Figure 33. The VP N / port table 30462 that manages this is also held.

VPN settings may also be managed by port and VLAN ID.

In this case, the VPN management table 3046 holds a port ZVPN table 30463 for managing the VPN ID for the port and the VLAN ID as shown in FIG. 34, and, as shown in FIG. 35, for the VPN ID and the VLAN. It also holds the VP NZ port table 30464 that manages the ports.

The table search unit 3030 acquires the output port information and the frame rewriting information with reference to the forwarding table storage unit 3 040 based on the header information, the frame type information, and the input port information received from the frame analysis unit 300.

The difference from the processing of the table search unit 330 will be described below.

(1) Frame type information is Ethernet (R) frame 4300 or VL

If the Ethernet (R) frame with AN tag is 4500 and the input port is the user terminal side port, refer to the VPN management table 3046 port ZVPN tape 30461 or 30463 and set the VPNID. E0 E—MAC address for MAC-DA and VL to be added with reference to MACZE o E—MAC table 342 in the forwarding table storage unit 3040

Get VLAN ID stored in AN tag.

Here, (1 1 1) If the target entry exists, the frame rewriting unit 3010 is notified of the acquired VP NID, EoE—MAC address and VLAN ID, and E o E— Indicates the stack of VLAN tags that store the VPN ID and VLAN ID. In addition, referring to the MAC table 341 of the forwarding table storage unit 3040, the acquired E o E-MAC address and the output port information for the VLAN are acquired. If there is a target entry, the frame transfer unit 320 is notified of the output port information. Conversely, if the target entry does not exist, refer to the broadcast table. The broadcast transfer port information is acquired, and the port information excluding the input port is notified to the frame transfer unit 320.

(1 -2) MAC—E o E—If there is no target entry in the MAC table 342, E oE—MAC—DA = broadcast or multicast, E o E-MAC 1 S A-Local Node E o E-MA

E o E in C—Indicates MAC header force pelling. It also indicates the stack of VLAN tags that store VLAN ID and VPN ID respectively. Also, by referring to the broadcast table 343 of the forwarding table storage unit 3040, the broadcast transfer port information for the VLAN ID is acquired, and the port information excluding the input port is notified to the frame transfer unit 320.

(2) The frame type information is EoE—MAC frame 4400 or VLAN tagged E o E—MAC frame 4600, the input port is the network side port, and the destination MAC address (E o E—MAC—DA address) is If the address is its own node, the following processing is performed.

(2 -2) Destination MAC address (E o E—MAC—DA address) is own node

In the case of 7 dresses, refer to the VPN / point table 304 62 or 30464 of the VPN management table 3046 to obtain the output port.

(2-2-1) If the target entry exists here, the output port information is notified to the frame transfer unit 1020, and one EoE MAC header and VLAN tags 1 and 2 are sent to the frame rewriting unit 3010. Instruct to delete.

(2-2-2-2) On the other hand, if the target entry does not exist, the broadcast forwarding port information for the VLAN ID is obtained by referring to the broadcast table 343, and the port information excluding the input port is sent to the frame forwarding unit 320. In addition to informing, the frame rewriting unit 3010 is instructed to delete the EoE—MAC header and VLAN tags 1 and 2.

(Effect of the fifth embodiment)

With the node configuration described above, the network shown in FIG.

Therefore, it is possible to perform transfer using the optimum route. (Sixth embodiment)

In the sixth embodiment, another optimum route transfer when a VPN is built between user terminals will be described.

In the fifth embodiment, a broadcast frame such as an unknown frame also flows on a route to which a terminal belonging to the VPN is not connected. In contrast, in this embodiment, a closed route is defined in the VPN and used together with the optimum route set in the first to fourth embodiments.

The broadcast route and multicast frame are transferred via the VPN route, and the route to be used is switched so that the unicast frame for which the destination is specified is transferred by the optimum route.

As a result, broadcast multicast frames can be closed and transferred to the same VPN while the unicast frames are transferred along the optimum route. FIG. 37 shows a route diagram for broadcast transfer according to the present embodiment.

In contrast to Figure 29 where VPN # A is set, as a transfer path for broadcast transfer between user terminals belonging to VPN # A, as shown in Figure 37, Edge Switch E1 and Edge Switch E3 Set the path to connect between the two via core switch C1. This transfer route shall be set manually by the network administrator or server.

By forwarding broadcast frames along this route, frames do not reach switches that are not related to VPN # A, and efficient and secure forwarding is possible.

The outline of the broadcast frame transfer processing procedure in the present embodiment is as shown in the flowchart of FIG.

Each switch receives a broadcast frame (step F— 1).

Referring to the forwarding table, obtain the output port corresponding to the VPN ID stored in the VL AN tag of the broadcast frame received in Step F-1 (Step F-2).

Frame is transmitted from the port acquired in Step F-2 (Step F-3). Note that the frame transfer processing procedure and the table setting processing procedure at the time of transferring the unicast frame according to this embodiment are the same as the respective procedures in the first to third embodiments, and thus description thereof is omitted. .

The detailed contents of the broadcast frame transfer processing procedure will be clarified in the following explanation of each component and its operation.

FIG. 38 shows a node configuration in the present embodiment.

FIG. 38 shows that the frame rewriting unit 3010 is the frame rewriting unit 38 10 and the table search unit 3030 is the table searching unit 3830 in the fifth embodiment in the node configuration shown in FIG. The forking table storage unit 3040 is changed to a foraging table storage unit 3840, and the other units are the same as those in FIG.

In the following, description will be made centering on the frame rewriting unit 3810, the table search unit 3830, and the forwarding table storage unit 3840 that are the differences from the fifth embodiment.

Frame rewrite section 3810 rewrites the frame for the main signal received frame received from frame analysis section 300 when instructed by table search section 3830.

Regarding frame rewriting, the difference from the processing in the frame rewriting unit 3010 is as follows.

The processing of the frame rewriting unit 3810 differs from the processing of the broadcast frame with respect to the frame rewriting unit 3010. The frame rewriting unit 3010 has both a unicast frame and a broadcast frame, together with EoE header encapsulation processing, a VLAN that stores an RS TP identifier (V LAN ID), and a VLAN that stores a VPN ID. In contrast to stacking two tags, the frame rewriting unit 3810 stacks only the VL AN tag that stores the VPN ID, together with the force oase processing of the EoE header, for the broadcast frame. When the header is deleted, the frame rewriting unit 3810 deletes the VLAN tag storing the VPN ID together with the decapsulation of the E o E—MAC header for the broadcast frame. Subsequently, the forwarding table storage unit 3840 has the same table as the forwarding table storage unit 3040 of FIG. 30, but the setting method of the broadcast table 343 is different.

The broadcast table 343 is stored in the forwarding table storage unit 3840, while it is set via the table control unit 390 based on the information of the STP control unit 380. In section 3840, the setting is performed via setting control section 395. As the setting contents, the route that passes only the switch related to the VPN ID is determined for VP N ID, and the port on the route is set.

The other tables (MAC table 341, MACZE o E—MAC table 342, VPN management table 3046) are retained in the same manner as the for- ding table storage unit 3040.

The processing of the table search unit 3830 is different from the table search unit 3030 regarding the handling of broadcast frames.

The difference from the processing of the table search unit 3030 is as follows.

(1) If the frame type information is Ethernet (R) frame 4300 or VL AN-tagged Ethernet (R) frame 4500, and the input port is the user terminal side port, the VPN management Port 3046 port ZVPN table 30461 or 30463 is referenced to obtain the VPNID and MAC / E o E in the forwarding table storage 3840—refer to MAC table 342 to refer to E o for MAC DA E—Obtain the MAC address and VLAN ID stored in the VL AN tag to be added.

Here, (1 1 1) If the target entry exists, the frame rewriting unit 3810 is notified of the obtained VP NID, EoE—MAC address and VLAN ID, and E o E— Indicates the stack of VLAN tags that store the VPN ID and VLAN ID, respectively. In addition, referring to the MAC table 341 of the forwarding table storage unit 3840, the acquired E o E-MAC address and the output port information for the VLAN are acquired. If the target entry exists here, the output port information is notified to the frame transfer unit 320. Conversely If there is no entry, the only VLAN tag to be stacked is the tag that stores the VP NID, and the broadcast table 343 is referenced to obtain the broadcast port forwarding port information for the VPN ID, excluding the input port. The port information is notified to the frame transfer unit 320.

(1 -2) MAC—E oE—If there is no target entry in MAC table 342, E o E—MAC—DA = Broadcast or Multicast, E o E—MAC — SA = Own node E o E— E o E in MA C—Indicates MAC header encapsulation. It also indicates the stack of the VL AN tag that stores the VPN ID. Also, refer to broadcast table 343 of forwarding table storage unit 3840, acquire broadcast transfer port information for VPN I; D, and frame the port information excluding the input port. Notify the data transfer unit 320.

(2) The frame type information is E o E—MAC frame 4400 or VL AN tagged E o E—MAC frame 4600, and the input port is the port on the network side, and the destination MAC address (E o E—MAC— If (DA address) is a self-node address, the following processing is performed.

(2-2) When the destination MAC address (E o E—MAC—DA address) is the local node address, refer to the VP NZ port table 304 62 or 30464 of the VPN management table 3046 to obtain the output port.

(2-2-1) If there is a target entry here, notify the frame transfer unit 320 of the output port information and delete the EoE—MAC header and VL AN tags 1 and 2 to the frame rewrite unit 3810. Direct (In the case of broadcast frames, it is the E oE—MAC header and the VL AN tag that are deleted).

(2-2-2) On the other hand, if the target entry does not exist, the broadcast forwarding port information for the VLAN ID is obtained by referring to the broadcast table 343, and the port information excluding the input port is sent to the frame forwarding unit. In addition to notifying 320, the frame rewriting unit 38 10 is instructed to delete the E o E—MAC header and VL AN tags 1 and 2 (In the case of a broadcast frame, the EoE MAC header and VLAN are deleted. Tag). Examples of forwarding of unicast frames and broadcast frames in consideration of VPN in the networks shown in FIGS. 29 and 37, which are composed of the switches having the node configuration described above, are described below.

An example of broadcast transfer from user terminal Τ1 in FIG. 37 for transfer between user terminals Tl and Τ3, and an example of unicast transfer from user terminal Τ3 to Τ1 in FIG. 29 will be described.

For tables with edge switch Ε 1, core switch C l, edge switch E 3 on the path, MAC table, MAC / E o E— The MAC table is shown in Figures 23-25. Use the same thing. In other words, edge switch E 1 has MAC table 2304, MACZE o E—MAC table 2305, core switch C 1 has MAC table 2404, edge switch E 3 has MAC table 2504, MAC / E o E—MAC table 2505 Holding.

Figure 39 summarizes the broadcast table and VPN management table.

Edge switch E 1 is broadcast table 3901, Port ZVPN table 3902, VPN / ⁷ port table 3903, Core switch C 1 is broadcast table 391 1, Edge switch E 3 is professional cast table Bull 3921, Portno VPN table 3922, VPN / port table 3923. In each of the broadcast tables 3901, 391 1, and 3 91, an entry for VPN ID == A is newly set. In the following description, since the detailed description inside each switch has been repeatedly described in the above embodiments, only the points will be described. -First, in Fig. 37, an example of broadcast transfer from user terminal T5 is shown.

When the edge switch E 5 receives the frame from the user terminal T 5 and determines that the received frame is to be broadcast-forwarded, the edge switch E 5 obtains the VPN ID = A for the input port = p 1 by referring to the port ZVPN table 46 01 Refer to the Yast Table 4600 to obtain the output port == p 2 for VPN ID = A, and the VLAN that stores E oE header force processing and VPN.ID = A Perform tag stack processing and transfer the frame to port p2.

The format of the E o E broadcast frame at this time is as shown in FIG.

The core switch C 1 that received the frame from the edge switch E 1 refers to the broadcast table 391 1 and the output port for VLAN ID = A = p 1,

2 is acquired, and the frame is transferred to port p 2 other than the input port.

The edge switch E 3 that received the frame from the core switch C 1 has the output port for VL AN ID = A other than input port = p 1 by referring to the broadcast table 3921, so refer to the VPNZ port table 3923 and VP Obtain the output port = p 2 for NID = A, delete the E o E header and the VL AN tag, and transfer the frame to port p 2.

With the above processing, broadcast transfer is possible only with the shortest route between edge switches connected to VPN # A.

Next, FIG. 29 shows an example in which the unicast transfer from the user terminal T 3 to T 1 is performed.

The edge switch E 3 that receives the frame addressed to the user terminal T 1 from the user terminal T 3 refers to MACZE o E—MAC table 2505, and E o E—MAC = e 1, VL for MAC_DA = t 1 Obtain AN ID = g 1 and refer to MAC table 2504 to obtain port p 1 as an output port for MAC = el (EoE—MAC = el) and VLAN ID = g 1. Also, VPN ID = A for input port = p 2 is obtained by referring to the point / VPN table 3922. Then, the frame is transferred to the port p 1 by performing the addition process of E o E—MAC—DA = e 1, VLAN ID = gl and VPN ID = A. The format of the E 0 E frame at this time is as shown in FIG.

Core switch C 1 that received the frame from edge switch E 1 obtains the output port = pl for MAC — DA = el, VL AN ID = 1, referring to MAC table 2404, and sends the frame to port p 1 Forward.

The edge switch E 3 that received the frame from the core switch C 1 has the VPNZ port table because EoE—M AC—DA = e 1 is equal to its own node E o E—MAC. B) Obtain output port p1 for VPN ID == A with reference to 3903, delete the E o E header and two VLAN tags, and then send a frame to port p1 Forward.

With the above processing, unicast transfer is possible on the shortest path between edge switches connected to VPN # A.

(Effect of the sixth embodiment)

As described above, in the data transfer method in the network constituted by the nodes of the present invention, the edge switch E o E is used in order to use the scanning tree in which the edge switch is the root node as the transfer path to the edge switch. — By resolving and maintaining the correspondence between the MAC address and the VLAN ID, which is the tree identifier, the shortest path is formed between all edge switches and can be transferred between all user terminals using the shortest path. is there. This eliminates traffic bias in the network, reduces the possibility of congestion, and makes it possible to efficiently use the network bandwidth.

In addition, according to this embodiment, both unicast transfer and broadcast transfer can be transferred on the shortest route, and in broadcast transfer, traffic between user terminals belonging to the same VPN is not related to VPN. Network bandwidth can be made more efficient because it is prevented from being transferred upward and is transferred only via the path between VPN-affiliated edge switches. In addition, since VPN traffic does not flow outside the same VPN, it is also effective in terms of security.

Claims

The scope of the claims

1. At the network node that forwards the data frame sent from the source terminal to the destination terminal,

Each node in the network maintains a correspondence relationship between an identifier of a node connected to the destination terminal and an identifier of a spanning tree having a node connected to the destination terminal as a root node,

An identifier of a node to which the destination terminal is connected and an identifier of the spanning tree are added to the data frame,

A node which determines an output port of the data frame from the correspondence relation using the spanning tree as a route.

2. The node to which the source terminal connects is connected to the data frame received from the source terminal by using the identifier of the node to which the destination terminal is connected as the destination address, and the node to which the source terminal is connected as the source address. And sending the data frame,

The node according to claim 1, wherein the data frame is forwarded on the spanning tree based on the added identifier of the node.

3. When determining the output port for the node connected to the destination terminal,

Of the spanning tree ports,

The port that is the root port and in the forwarding state is defined as the output port of the unicast frame.

The node according to claim 1 or 2, wherein a port that is an assigned point and is in a forwarding state or a learning state is set as an output port of a broadcast frame.

4. Each node holds a table in which a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree is preset. The node according to any one of claims 1 to 3.

5. A correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree is generated from information included in a predetermined control frame transferred on a network in the creation of the spanning tree. The node according to any one of claims 1 to 3.

6. The identifier of the node to which the destination terminal is connected is set so that the identifier of the node to which the destination terminal is connected can be obtained by performing a predetermined operation on the identifier of the spanning tree.

By performing a predetermined calculation on the spanning tree identifier acquired from the received data frame, an identifier of the node to which the destination terminal is connected is obtained, and the identifier of the node to which the destination terminal is connected and the spanning tree The node according to any one of claims 1 to 3, wherein a correspondence relationship between identifiers is acquired.

7. A table that records the correspondence relationship between the identifier of the node to which the destination terminal is connected and the identifier of the sub-spanning tree is stored, and based on the notification information from the sub-spanning tree control unit that processes the sub-spanning tree The identifier of the node to which the destination terminal is connected is acquired from the notified identifier of the spanning tree, and the output port for the node to which the acquired destination terminal is connected is set to the port acquired from the spanning tree control unit. A table control unit for writing to the forwarding table;

In the Housugingu table,

Storing a table holding an output port for an identifier of a node to which the destination terminal is connected, and a table holding a broadcast output port for an identifier of the sub-banding tree or an identifier for identifying a VPN. The node according to any one of claims 1 to 3.

8. In the table control unit, the identifier of the node to which the destination terminal is connected and the spa 8. The node according to claim 7, wherein a table for recording a correspondence relation between identifiers of the ning tree is manually set.

9. After the spanning tree process is complete, transfer the specified control frame onto the spanning tree.

The table control unit obtains a correspondence relationship between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree from the information stored in the received control frame, and the table of the node to which the destination terminal is connected. The node according to claim 7, wherein the node is stored in a table that records a correspondence relationship between an identifier and an identifier of the sub-spanning tree.

1 0. Acquires the correspondence between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree from the information stored in a predetermined control frame transferred on the spanning tree;

The node according to claim 7, wherein the table control unit stores the acquired correspondence information in a table that records a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree. .

1 1. The table control unit calculates the identifier of the node to which the destination terminal is connected from the obtained identifier of the spanning tree, and the correspondence between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree 8. The relationship is acquired, and the acquired correspondence relationship information is stored in a table that records a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree. The listed node.

1 2. The node connected to the destination terminal

The identifier of the own node is stored as a transmission source address, and a data frame to which data storing the identifier of a spanning tree in which the own node is a root node is transmitted is transmitted. Node described in.

1 3. A node other than the node connected to the destination terminal

3. The port according to claim 1, wherein the port receiving the data frame sent by the node connected to the destination terminal is used as an output port for the node connected to the destination terminal. Item 1 The node according to any one of 2 above.

1 4. If the identifier of the node connected to the destination terminal of the data frame received from the source terminal is unknown, the identifier of the own node is stored as the source address, and the spanning tree A table search unit for determining creation and transmission of a data frame to which the data storing the identifier is added;

A MAC learning unit having an output port for a combination of a node identifier stored in a transmission source address of a reception data frame and a spanning tree identifier as a reception port of the reception data frame; The node according to claim 1.

1 5. When the source terminal and the destination terminal that transmit and receive data frames form a network based on another protocol,

The data for storing an identifier for identifying a network based on the other protocol is added to the data frame together with data for storing the identifier of the spanning tree. One of the nodes.

1 6. A table holding network identifiers according to other protocols for data frame reception points, or a table holding network identifiers according to other protocols for data frame reception ports and spanning tree identifiers. The node according to claim 15, characterized by comprising:

1 7. When the source terminal and the destination terminal that transmit and receive data frames form a network with another protocol,

When the overnight frame is a unicast frame, Along with data for storing a single identifier, data for storing an identifier for identifying a network according to another protocol is added to the data frame, and the spanning tree is used as a transfer path,

When the data frame is a multicast frame or a broadcast frame, data for storing an identifier for identifying a network based on the other protocol is added to the data frame, and the data frame belongs to the network based on the other protocol. The node according to any one of claims 1 to 14, wherein a transfer path set for a terminal is used.

1 8. A table that holds network identifiers according to other protocols for data frame reception ports, or a table that holds network identifiers according to other protocols for data frame reception ports and spanning tree identifiers.

The table search unit

When the data frame is a unicast frame, creation of a data frame to which data for storing an identifier for identifying a network according to another protocol is added together with data for storing the identifier of the scanning tree. When transmission is decided, and when the data frame is a multicast frame or broadcast frame, creation and transmission of a data frame to which data for storing an identifier for identifying a network according to the other protocol is added are decided. The node according to claim 17, characterized by:

1 9. The node according to any one of claims 15 to 18, characterized in that the network according to another protocol is V PN.

20. The node according to claim 1, wherein an identifier of a node to which the destination terminal is connected is an E o E—MAC address.

2 1. Between a source terminal and a destination terminal that include multiple nodes and are connected to the node In a network that transfers data frames,

Each node in the network has a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of a sub-tree that uses the node connected to the destination terminal as a root node,

An output port for the node to which the destination terminal is connected is determined from the correspondence relationship on the spanning tree based on the port information of the spanning tree, and the data frame is forwarded. Iku.

2 2. The node to which the source terminal is connected connects the identifier of the node to which the destination terminal is connected as the destination address to the data frame received from the source terminal, and the source terminal as the source address. Add the node identifier, send the data frame,

The network according to claim 21, wherein a data frame is forwarded on the spanning tree based on the identifier of the added node.

2 3. When determining the output port for the node connected to the destination terminal, out of the spanning tree ports,

The port that is the root port and in the forwarding state is the output port of the unicast frame,

3. The network according to claim 21, wherein a port that is an assigned port and is in a forwarding state or a learning state is set as an output port of a broadcast frame.

24. A table in which a correspondence relationship between an identifier of a node connected to the destination terminal and an identifier of the spanning tree is preset in each node is held in each node. 2 The network according to any one of 3 above.

25. Information contained in a predetermined control frame transferred by the node over the network in the creation of the spanning tree, the correspondence relationship between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree. The network according to any one of claims 21 to 23, wherein the network is generated from the network.

26. Set the identifier of the node to which the destination terminal is connected so that the identifier of the node to which the destination terminal is connected can be obtained by performing a predetermined operation on the identifier of the spanning tree.

The node obtains the identifier of the node to which the destination terminal is connected by performing a predetermined operation on the identifier of the sub-banding tree acquired from the received overnight frame, and the identifier of the node to which the destination terminal is connected The network according to any one of claims 21 to 23, wherein a correspondence relationship between the identifier and the identifier of the spanning tree is acquired.

27. A table that records the correspondence between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree is stored in the node, and notification information from the spanning tree control unit that performs the processing of the spanning tree is stored in the node. Based on the notification, the identifier of the node connected to the destination terminal is acquired from the identifier of the above-mentioned Banning Tree, and the output port for the node connected to the acquired destination terminal is acquired from the spanning tree control unit. With a table control unit that writes to the forwarding table,

In the forwarding table,

A table holding an output port for an identifier of a node to which the destination and terminal are connected, and a table holding a broadcast output port for an identifier of the spanning tree or an identifier for identifying a VPN. The network according to any one of claims 21 to 23, characterized by:

28. The table controller manually sets a table for recording the correspondence between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree. The network according to claim 27, wherein:

2 9. After the processing of the spanning tree is completed, the predetermined control frame is reached on the spanning tree,

The table control unit obtains a correspondence relationship between the identifier of the node connected to the destination terminal and the identifier of the spanning tree from the information stored in the received control frame, and the node to which the destination terminal connects 28. The network according to claim 27, wherein the network is stored in a table that records a correspondence relationship between the identifier of the spanning tree and the identifier of the spanning tree.

3 0. Acquires a correspondence relationship between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree from information stored in a predetermined control frame transferred on the spanning tree;

28. The table control unit stores the acquired correspondence information in a table that records a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree. Network.

3 1. The table control unit calculates the identifier of the node to which the destination terminal is connected from the acquired identifier of the spanning tree, and the correspondence between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree The relationship is acquired, and the acquired correspondence information is stored in a table that records a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree. The network described.

3 2. The node connected to the destination terminal

The identifier of the own node is stored as a transmission source address, and a data frame to which the identifier of the sub-tree that is the root node is stored is sent, and the data frame is transmitted. Item 2 The network according to 2.

3 3. A node other than the node connected to the destination terminal

The port receiving the data frame transmitted by the node connected to the destination terminal is used as an output port for the node connected to the destination terminal. Item 3 The network according to any one of items 2 to 3.

3 4. When the identifier of the node connected to the destination terminal of the data frame received from the source terminal is unknown, the identifier of the own node is stored as the source address, and the switching node that is the root node of the own node is stored. A table search unit for determining the creation and transmission of a data frame with the identifier stored data,

A MAC learning unit having an output port for a combination of a node identifier stored in a transmission source address of a received data frame and a spanning tree identifier as a reception port of the received data frame. 3 The network described in 3.

3 5. When the source terminal and the destination terminal that transmit and receive data frames form a network based on another protocol,

The data for storing an identifier for identifying a network based on the other protocol is added to the data frame together with the data for storing the identifier for the spanning tree. One of the nets listed in 4

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3 6. Table that holds the network identification by the other protocol for the receiving port of the data frame, or the table that holds the network identifier by the other protocol for the receiving port of the overnight frame and the identifier of the spanning tree. The network according to claim 35, characterized by comprising:

3 7. When the source terminal and the destination terminal that transmit and receive data frames form a network based on another protocol,

When the data frame is a unicast frame, Along with data for storing a single identifier, data for storing an identifier for identifying a network according to another protocol is added to the data frame, and the spanning tree is used as a forwarding path.

When the data frame is a multicast frame or a broadcast frame, data for storing an identifier for identifying a network based on the other protocol is added to the data frame, and for terminals belonging to the network based on the other protocol. The network according to any one of claims 21 to 34, wherein the transfer path set in (1) is used.

3 8. Table holding network identifiers by other protocols for data frame reception ports, or network identifiers by other protocols for data frame receiving ports and spanning tree identifiers Have a table,

The table search unit

When the data frame is a unicast frame, the data frame of the data frame with the data storing the identifier of the spanning tree and the data storing the identifier identifying the network according to another protocol is added. If the data frame is a multicast frame or a broadcast frame, creation and transmission of a data frame to which data for storing an identifier for identifying a network based on the other protocol is added is determined. The network according to claim 37, wherein the network is determined.

The network according to any one of claims 35 to 38, characterized in that the network according to the other protocol is VPN.

40. The network according to any one of claims 21 to 39, wherein an identifier of a node to which the destination terminal is connected is an E o E—MAC address. .

4 1. A method for creating a correspondence relationship of transfer information in a network in which a data frame sent from a source terminal is transferred to a destination terminal.

An identifier of a node to which the destination terminal is connected and an identifier of a sub-banding tree with a node connected to the destination terminal as a root node are added to the data frame, and the destination terminal is connected to each node in the network. A correspondence relationship between a node identifier and a identifier of a spanning tree having a node connected to the destination terminal as a root node, and the node connected to the destination terminal based on port information of the spanning tree A transfer information correspondence creation method, comprising: creating a correspondence for determining an output port of the data frame to be transferred.

42. A table in which the correspondence between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree is set in advance is held in each node. Correspondence creation method.

4 3. Generating the correspondence between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree from information contained in a predetermined control frame transferred on the network in the creation of the spanning tree. The transfer information correspondence creation method according to claim 41, wherein the transfer information correspondence relationship is defined as follows.

4 4.Set the identifier of the node to which the destination terminal is connected so that the identifier of the node to which the destination terminal is connected can be obtained by performing a predetermined operation on the identifier of the spanning tree.

By performing a predetermined operation on the identifier of the sub-banding tree acquired from the received data frame, the identifier of the node to which the destination terminal is connected is obtained, and the identifier of the node to which the destination terminal is connected and the sub-banding 4. The transfer information correspondence creation method according to claim 41, wherein a correspondence relationship between tree identifiers is created.

4 5. Maintains a table that records the correspondence between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree, and performs the processing of the spanning tree. に Based on the notification information from the spanning tree control unit, the identifier of the node to which the destination terminal is connected is acquired from the notified identifier of the spanning tree, and the acquired node to which the destination terminal is connected Set the output port to the port acquired from the spanning tree control unit, write to the forwarding table,

A table holding an output port for an identifier of a node to which the destination terminal is connected and a table holding a broadcast output port for an identifier of the sub-banding tree or an identifier for identifying a VPN. And the transfer information correspondence creating method according to claim 41.

46. The transfer information correspondence creation according to claim 45, wherein a table for recording a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree is manually set. Method.

4 7. After completing the spanning tree processing, place a predetermined control frame on the spanning tree,

The correspondence relationship between the identifier of the node to which the destination terminal connects and the identifier of the sub-spanning tree is obtained from the information stored in the received control frame, and the identifier of the node to which the destination terminal connects and the sub-spanning tree The transfer information correspondence creation method according to claim 45, wherein the correspondence relation of identifiers is stored in a table for recording the correspondence.

4 8. Obtaining the correspondence between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree from the information stored in a predetermined control frame transferred on the spanning tree,

The transfer information correspondence relationship according to claim 45, wherein the acquired correspondence relationship information is stored in a table that records a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree. How to make.

4 9. The identifier of the node to which the destination terminal is connected is calculated from the acquired identifier of the spanning tree, and the correspondence relationship between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree is obtained. 46. The correspondence relationship of transfer information according to claim 45, wherein the correspondence relationship information is stored in a table that records a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the sub-spanning tree. How to make.

5 0. The node connected to the destination terminal is

Data that stores the identifier of the own node as the source address and adds the data that stores the identifier of the spanning tree in which the own node is the root node. The transfer information correspondence creation method according to item 4 1 or claim 4 2.

5 1. A node other than the node connected to the destination terminal

The port receiving the data frame transmitted by the node connected to the destination terminal is used as an output port for the node connected to the destination terminal. Item 50. The transfer information correspondence creation method according to any one of items 1 to 5.

5 2. If the identifier of the node connected to the destination terminal of the data frame received from the source terminal is unknown, the identifier of the own node is stored as the source address, and the spanning tree Decide whether to create and send a data frame with an identifier stored,

The output port for the combination of the node identifier stored in the transmission source address of the reception data frame and the identifier of the spanning tree is used as the reception port of the reception data frame. How to create a correspondence relationship for the described transfer information.

5 3. The source terminal and the destination terminal that transmit and receive data frames are If you have a network with a protocol,

The data storing the identifier for identifying the network based on the other protocol is added to the data frame together with the data storing the identifier of the spanning tree. Or the transfer information correspondence creation method described in item 1.

5 4. A table that holds network identifiers according to other protocols for data frame reception points, or a table that holds network identifiers according to other protocols for data frame reception ports and spanning tree identifiers. The transfer information correspondence creation method according to claim 53, wherein the transfer information correspondence relation creation method is created.

5 5. When the source terminal and the destination terminal that transmit and receive data frames form a network with another protocol,

When the data frame is a unicast frame, data for storing an identifier for identifying a network according to another protocol is added to the data frame together with data for storing the identifier of the spanning tree. Using spanning green as a transfer path,

When the data frame is a multicast frame or a broadcast frame, a data storing an identifier for identifying a network based on the other protocol is added to the data frame based on the other protocol. 5. The transfer information correspondence creation method according to claim 41, wherein a transfer route set for a terminal belonging to the network is used.

5 6. A table holding network identifiers by other protocols for data frame receiving ports, or a table holding network identifiers by other protocols for data frame receiving ports and spanning tree identifiers. ,

When the data frame is a unicast frame, the spanking It decides to create and transmit a data frame with data storing an identifier for identifying a network together with an identifier for identifying a network according to another protocol, and the data frame is a multicast frame or a broadcast frame. The transfer information correspondence creation according to claim 55, characterized in that, in some cases, it is determined to create and send a data frame to which data for storing an identifier for identifying a network based on the other protocol is added. Method.

5 7. A frame transfer program executed on a computer that is a network node for transferring data frames between a source terminal and a destination terminal, the identifier of a node to which the destination terminal is connected, and the destination terminal Maintain the correspondence of the identifiers of the spanning tree with the connected node as the root node,

An identifier of a node connected to the destination terminal and an identifier of the spanning tree are added to the data frame;

On the spanning tree, based on the port information of the spanning tree, an output port for the node to which the destination terminal is connected is determined from the correspondence relationship, and the function of transferring the overnight frame is realized in the node. A frame transfer program characterized by

5 8. To the node to which the source terminal is connected,

The data frame received from the source terminal is appended with the identifier of the node to which the destination terminal is connected as the destination address, and the identifier of the node to which the source terminal is connected as the source address, and the data frame is transmitted. ,

The frame transfer program according to claim 57, wherein a function for transferring a de-evening frame is executed on the spanning tree based on the added identifier of the node.

5 9. When determining an output port for a node connected to the destination terminal, among the spanning tree ports,

If the port is the root port and the status is forwarding, As the output port of the strike frame,

The frame according to claim 57 or 58, wherein a function of setting an assigned port that is in a forwarding state or a running state as an output port of a broadcast frame is executed. Transfer program.

60. The function of causing each node to execute a function of holding a table in which a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree is set in advance is set in each node. The frame transfer program according to any one of claims 59.

6 1. The correspondence relationship between the identifier of the node to which the destination terminal is connected and the identifier of the sub-banding tree is included in the predetermined control frame transferred on the network in the creation of the sub-banding tree. The frame transfer program according to any one of claims 57 to 59, wherein a function generated from the generated information is executed.

6 2. Set the identifier of the node to which the destination terminal is connected so that the identifier of the node to which the destination terminal ′ is connected can be obtained by performing a predetermined operation on the identifier of the spanning tree.

The node performs a predetermined operation on the spanning tree identifier obtained from the received data frame to obtain the node identifier to which the destination terminal is connected, and the node identifier to which the destination terminal is connected and the spanning tree The frame transfer program according to any one of claims 57 to 59, wherein a function for acquiring a correspondence relationship of one identifier is executed.

6 3. A table storing a correspondence relationship between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree is stored in the node, and notification information from a spanning tree control function for performing the processing of the spanning tree is also stored. The identifier of the node to which the destination terminal is connected is obtained from the notified identifier of the spanning tree. A table control function for setting the output port for the node to which the acquired destination terminal is connected to the port acquired from the spanning tree control unit, and writing to the forwarding table;

In the forwarding table,

A function of executing a function of holding a table holding an output port for an identifier of a node to which the destination terminal is connected and a table holding a broadcast output port for an identifier of the sub-banding identifier or an identifier for identifying a VPN. The frame transfer program according to any one of claims 5 7 to 59.

6 4. The frame transfer according to claim 63, wherein the table control function manually sets a table for recording a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree. program.

6 5. After the processing of the spanning tree is completed, a predetermined control frame is reached on the spanning tree.

The table control function obtains the correspondence relationship between the identifier of the node to which the destination terminal is connected and the spanning tree identifier from the information stored in the received control frame, and The frame transfer program according to claim 63, wherein the frame transfer program is stored in a table that records a correspondence relationship between an identifier and the identifier of the spanning tree.

6 6. Obtaining the correspondence between the identifier of the node connected to the destination terminal and the identifier of the spanning tree from the information stored in a predetermined control frame transferred on the previous spanning tree,

7. The table control function stores the acquired correspondence information in a table that records a correspondence relationship between an identifier of a node to which the destination terminal is connected and an identifier of the spanning tree. 3. The frame transfer program according to 3.

6 7. The table control function calculates the identifier of the node to which the destination terminal is connected from the acquired identifier of the spanning tree, and the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree. The correspondence relationship information is acquired, and the acquired correspondence relationship information is stored in a table that records the correspondence relationship between the identifier of the node to which the destination terminal is connected and the identifier of the spanning tree. The frame transfer program described in 3.

6 8. To the node connected to the destination terminal,

It stores the identifier of its own node as the transmission source address, and executes the function of sending a data frame to which the data storing the identifier of the spanning tree whose own node is the root node is added. The frame transfer program according to claim 5 7 or claim 58.

6 9. To nodes other than the node connected to the destination terminal,

The function of setting the port that has received the data frame transmitted by the node connected to the destination terminal as an output port for the node connected to the destination terminal is executed. Or the frame transfer program according to any one of claims 68.

7 0. When the identifier of the node connected to the destination terminal in the data frame received from the source terminal is unknown, the identifier of the own node is stored as the source address, and the spanning tree A table search function for deciding whether to create and send a data frame with data stored with

The MAC learning mechanism is executed, wherein an output port corresponding to a combination of a node identifier stored in a transmission source address of a received data frame and an identifier of a spanning tree is used as a reception port of the received data frame. 6 Frame transfer program according to 9.

7 1. The source terminal and the destination terminal that send and receive data tasram If you have a network with a protocol,

The function of adding data for storing an identifier for identifying a network based on the other protocol together with data for storing the identifier of the spanning tree to the data frame is executed. Item 70. The frame transfer program according to any one of items 0 to 10.

7 2. A table holding network identifiers by other protocols for data frame receiving ports, or network identifiers by other protocols for data receiving port and spanning tree identifiers. The frame transfer program according to claim 71, further comprising a table to be held.

7 3. When the source terminal and the destination terminal that transmit and receive data frames form a network based on another protocol,

When the data frame is a unicast frame, data storing an identifier for identifying a network by another protocol is added to the data frame together with data storing the identifier of the scanning tree. The spanning tree is used as a transfer path,

When the data frame is a multicast frame or a broadcast frame, data storing an identifier for identifying a network based on the other protocol is added to the data frame, and the data frame belongs to a network based on the other protocol. The frame transfer program according to any one of claims 57 to 70, wherein a function that uses a transfer path set for a terminal is executed.

7 4. It has a table that holds network identifiers according to other protocols for data frame reception ports, or a table that holds network identifiers according to other protocols for data frame reception ports and spanning tree identifiers.

When the data frame is a unicast frame, the spanning packet is Together with the data to store the identifier of the network, it decides to create and send a data frame to which data for storing the identifier for identifying the network according to another protocol is added, and the data frame is a multicast frame or broadcast. The function of determining the creation and transmission of a data frame to which data for storing an identifier for identifying a network based on the other protocol is added in the case of a frame is provided. Frame transfer program.