IP over ATM system using control messages to set up cut-through paths or bypass pipes in routers

• US 6,343,322 B2
• Filed: 07/27/1998
• Issued: 01/29/2002
• Est. Priority Date: 08/31/1994
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Saito, Takeshi, Ami, Junko, Nagami, Kenichi, Katsube, Yasuhiro, Esaki, Hiroshi
• Primary Examiner(s): Maung, Zarni
• Assistant Examiner(s): Caldwell, Andrew
• Application Number:
  US09/122,644
• Publication Number:
  US 20010056490A1
• Time in Patent Office: 1,282 Days
• Field of Search: 709/220, 709/223, 709/227, 709/249, 709/250, 710/36-38, 710/129-131, 370/248, 370/351, 370/389, 370/392, 370/396-406, 370/420, 370/431, 370/437, 340/825, 340/825.03, 340/826
• US Class Current: 709/227
• CPC Class Codes: H04L 12/4608 LAN interconnection over ATM networks
• CPC Class Codes: H04L 2012/562 Routing
• CPC Class Codes: H04L 2012/5667 IP over ATM
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections

Abstract

A packet transfer scheme for transferring packets at a boundary of a plurality networks is disclosed. A network interconnection apparatus (router) communicates with a previous hop node in one of the plurality of networks by a first control message including a first identification information for identifying an upstream path from the previous hop node and a specification information for specifying a group of packets to be transferred on the upstream path, and with a next hop node in another of the plurality of networks by a second control message including a second identification information for identifying a downstream path to the next hop node and a specification information for specifying a group of packets to be transferred on the downstream path. Then, the network interconnection apparatus stores a first identifier at a layer lower than layer 3 of the upstream path and a second identifier at a layer lower than layer 3 of the downstream path corresponding to the upstream path, according to the first and second control messages, and transfers a packet from the upstream path to the corresponding downstream path, referring to the memory.

Claims

1. A network interconnection apparatus for transferring packets at a boundary of a plurality of networks, the apparatus comprising:

a control message processing unit configured to communicate with a previous hop node in one of the plurality of networks by a first control message including a first identification information for identifying an upstream path from the previous hop node to the network interconnection apparatus and a specification information for specifying a group of packets to be transferred on the upstream path, and configured to communicate with a next hop node in another of the plurality of networks by a second control message including a second identification information for identifying a downstream path from the network interconnection apparatus to the next hop node and a specification information for specifying a group of packets to be transferred on the downstream path;

a memory unit configured to store a first identifier at a layer lower than layer 3 of the upstream path and a second identifier at a layer lower than layer 3 of the downstream path corresponding to the upstream path, according to the first and second control messages used by the control message processing unit; and

a transfer unit configured to transfer a packet from the upstream path to the corresponding downstream path, referring to the memory unit.

2. The apparatus according to claim 1, further comprising:

another memory unit configured to store a destination information including a layer 3 address regarding a destination and a corresponding next hop information,

wherein the control message processing unit communicates with the next hop node according to the destination information and the corresponding next hop information stored in said another memory unit.

3. The apparatus according to claim 2, wherein the control message processing unit starts to communicate with at least one of the next hop node and the previous hop node when said another memory unit indicates a new information based on a routing protocol.

4. The apparatus according to claim 2, further comprising a transfer processing unit configured to transfer a packet to the next hop node, referring to said another memory unit according to a layer 3 address regarding a destination of the packet.

5. The apparatus according to claim 4, further comprising a receiving unit configured to receive a packet through a virtual connection, and to transfer the packet to the transfer unit when said memory unit stores an identifier of the virtual connection as the first identifier that corresponds to the second identifier and otherwise transfer the packet to the transfer processing unit.

6. The apparatus according to claim 5, wherein the receiving unit transfers a packet to the transfer processing unit when the packet is received through a prescribed virtual connection, and the control message processing unit processes the first control message indicating another virtual connection other than the prescribed virtual connection as the upstream path.

7. The apparatus according to claim 1, wherein the transfer unit uses a first virtual connection as the upstream path and a second virtual connection as the downstream path.

8. The apparatus according to claim 7, wherein the memory unit stores an identifier of the first virtual connection as the first identifier and an identifier of the second virtual connection as the second identifier.

9. The apparatus according to claim 8, wherein, when at least one of the first and second virtual connections pass through a switch for switching virtual connections, the control message processing unit uses an identification information for identifying said at least one of the first and second virtual connections uniquely in a corresponding one of the plurality of networks.

10. The apparatus according to claim 9, further comprising a setup unit configured to set up said at least one of the first and second virtual connections by signaling before the memory unit stores a corresponding one of the first and second identifiers as available for the transfer unit.

11. The apparatus according to claim 1, wherein the control message processing unit uses at least one of addresses regarding a source or a destination of the group of packets to be transferred as the specification information.

12. The apparatus according to claim 1, wherein the transfer unit transfers another packet from the upstream path to the corresponding downstream path, said packet being toward one destination and said another packet being toward another destination, both said packet and said another packet belonging to the group of packets.

13. The apparatus according to claim 1, wherein the control message processing unit uses the first identifier to be stored in the memory unit as the first identification information, and uses the second identifier to be stored in the memory unit as the second identification information.

14. The apparatus according to claim 1, wherein the control message processing unit starts to communicate with one of the next hop node and the previous hop node when the other of the next hop node and the previous hop node starts to communicate with the network interconnection apparatus.

15. The apparatus according to claim 1, wherein the control message processing unit starts to communicate with one of the next hop node and the previous hop node when the network interconnection apparatus receives a packet from the previous hop node or transmits a packet to the next hop node.

16. The apparatus according to claim 1, wherein the control message processing unit starts to communicate with one of the next hop node and the previous hop node according to statistical information regarding transferring packets to the next hop node.

17. The apparatus according to claim 1, wherein the control message processing unit communicates with another previous hop node by a third control message including a third identification information for identifying another upstream path from said another previous hop node to the network interconnection apparatus and a specification information for specifying a group of packets to be transferred on said another upstream path, and the memory unit stores a third identifier at a layer lower than layer 3 of said another upstream path, such that the first and third identifiers are stored in correspondence with the second identifier.

18. The apparatus according to claim 17, wherein the transfer unit transfers all packets of one protocol data unit from the upstream path of the first identifier or said another upstream path of the third identifier to the downstream path of the second identifier before starting to transfer a packet of another protocol data unit.

19. The apparatus according to claim 1, wherein the memory unit stores the second identifier while communication regarding the second control message is repeated and deletes the second identifier when the communication regarding the second control message stops for a predetermined period.

20. The apparatus according to claim 1, wherein the memory unit deletes the second identifier when a delete control message is received from at least one of the next hop node and the previous hop node.

21. The apparatus according to claim 1, wherein the memory unit deletes the first identifier when a packet from the upstream path of the first identifier is not received for a predetermined period.

22. A method of transferring packets at a boundary of a plurality of networks, the method comprising the steps of:

communicating with a previous hop node in one of the plurality of networks by a first control message including a first identification information for identifying an upstream path from the previous hop node and a specification information for specifying a group of packets to be transferred on the upstream path;

communicating with a next hop node in another of the plurality of networks by a second control message including a second identification information for identifying a downstream path to the next hop node and a specification information for specifying a group of packets to be transferred on the downstream path;

storing, in a memory, a first identifier at a layer lower than layer 3 of the upstream path and a second identifier at a layer lower than layer 3 of the downstream path corresponding to the upstream path, according to the first and second control messages; and

transferring a packet from the upstream path to the corresponding downstream path, referring to the memory.

23. The method according to claim 22, further comprising:

storing, prior to the step of communicating with the next hop node, a destination information including a layer 3 address regarding a destination and a corresponding next hop information in another memory,

wherein the step of communicating with the next hop node communicates according to the destination information and the corresponding next hop information stored in said another memory.