Packet transferring method and apparatus that employs the same

• US 20030043802A1
• Filed: 08/05/2002
• Published: 03/06/2003
• Est. Priority Date: 08/31/2001
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yazaki, Takeki, Kanada, Yasusi
• Granted Patent: US 7,376,085 B2
• Time in Patent Office: Days
• US Class Current: 370/389
• CPC Class Codes: H04L 41/5022 by giving priorities, e.g. assigning classes of service
• CPC Class Codes: H04L 43/026 using flow identification
• CPC Class Codes: H04L 43/0894 Packet rate
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/7453 using hashing
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/20 Traffic policing
• CPC Class Codes: H04L 47/2433 Allocation of priorities to traffic types
• CPC Class Codes: H04L 47/2441 relying on flow classification, e.g. using integrated services [IntServ]
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

Every router in a network is provided with flow detecting means that detects a flow from a packet header of a packet so as to perform such packet processings as bandwidth monitoring, priority-based transferring, statistical information collecting with respect to each packet flow. Receiving a packet from a site, an edge router detects the packet flow and writes a flow identifier in the packet. Each flow identifier is uniquely decided in the network. The Internet router performs such packet processings as bandwidth monitoring, priority-based transferring, statistical information collecting with respect to each flow according to the flow identifier. The present invention can thus prevent the network from degradation of transferring performance caused by the flow detecting means of a backbone router.

Claims

1. A packet processing method employed in an IP network provided with a plurality of nodes, the method comprising:

a step of enabling a first node to decide a flow ID according to information written in a header of a received packet so as to write the flow ID in the packet, the flow ID being used to identify a flow to which the packet belongs; and

a step of enabling a second node that receives the packet from the first node to perform at least one of such packet processings as bandwidth monitoring, statistical information collecting, filtering, and priority-based transferring according to the flow ID.

2. The packet processing method according to claim 1, wherein the first-node enabling step includes a step of enabling the first node to decide a new flow ID according to the flow ID written in the header so as to identify a packet flow to write therein the new flow ID.

13. The packet processing method according to claim 2, wherein the second-node enabling step includes a step of enabling the second node to performs said at least one packet processing on all flows of a flow bundle collectively.

14. The packet processing method according to claim 2, wherein the new flow ID is decided by the flow ID in conjunction with the information written in the header.

15. The packet processing method according to claim 2, wherein each flow is decided with one unique new flow ID.

16. The packet processing method according to claim 1, wherein the first node is an edge router and the second node is a backbone router located downstream from the first node.

18. The packet processing method according to claim 1, wherein each flow is decided with one unique flow ID.

3. A packet transferring apparatus that outputs a packet inputted from any one of a plurality of input lines and outputs the inputted packet to any one of a plurality of output lines, the apparatus comprising:

flow detecting means for deciding a flow ID that is an identifier of a flow to which the inputted packet belongs according to information written in a header of the packet; and

a flow processing means for performing at least one of such packet processings as bandwidth monitoring, statistical information collecting, filtering, and priority-based transferring according to the flow ID.

4. The packet transferring apparatus according to claim 3, wherein the flow detecting means includes:

an contents addressable memory having a plurality of flow entries, each including information written in a packet header, the memory determines a matching/unmatching between the header information of each inputted packet and each of the plurality of flow entries so as to output matching addresses which are addresses of matched flow entries; and

an address translating means for translating a plurality of the matching addresses to one flow ID.

5. The packet transferring apparatus according to claim 4, wherein the address translating means includes:

an address translation table that stores a flow ID for each of the matching addresses; and

an address translation table controlling means for inputting each of the matching addresses as an address for reading information from the address translation table.

6. The packet transferring apparatus according to claim 3, wherein the flow detecting means includes:

means provided with an entry table stored with a plurality of entries, each entry comprising of a flow ID and at least one flow condition which includes information written in a header of each inputted packet, said means is constructed to decide a matching/unmatching between the flow condition of each entry and the header upon an input of header information and to decide the flow ID described in a matched entry as the flow ID of the inputted packet.

8. The packet transferring apparatus according to claim 3, wherein each flow is decided with one unique flow ID.

9. The packet transferring apparatus according to claim 3, wherein the flow detecting means includes means for deciding a new flow ID according to the flow ID written in the header so as to identify a packet flow of a flow bundle to write therein the new flow ID.

10. The packet transferring apparatus according to claim 9, wherein the second node performs said at least one packet processing on all flows of the flow bundle collectively.

11. The packet transferring apparatus according to claim 9, wherein the new flow ID is decided by the flow ID in conjunction with source site information included in the header information.

12. The packet transferring apparatus according to claim 9, wherein each flow is decided with one unique new flow ID.

17. The packet transferring apparatus according to claim 3, wherein a same flow ID is assigned to a plurality of flows.

20. The packet transferring apparatus according to claim 3, wherein the flow ID is also an identifier of a flow bundle to which the flow belongs.

7. A packet transferring apparatus provided with a plurality of input lines and a plurality of output lines and enabled to output a packet inputted from any one of the plurality of input lines to any one of a plurality of output lines, the apparatus including:

first flow detecting means that decides a first flow ID, which is an identifier of a flow to which an inputted packet belongs according to information written in a header of the inputted packet;

second flow detecting means that decides a second flow ID of a flow bundle according to the first flow ID and the information written in the header; and

a flow processing means for performing at least one of such packet processings as bandwidth monitoring, statistical information collecting, filtering, and priority-based transferring according to the second flow ID.

19. The packet transferring apparatus according to claim 7, wherein each flow is decided with one unique flow ID.