Network relay apparatus and method of combining packets

• US 20010055317A1
• Filed: 03/14/2001
• Published: 12/27/2001
• Est. Priority Date: 06/21/2000
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Suzuyama, Shigeru, Kajizaki, Noriki, Tokunaga, Akira
• Granted Patent: US 7,274,711 B2
• Time in Patent Office: Days
• US Class Current: 370/474
• CPC Class Codes: H04L 2212/00 Encapsulation of packets
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/36 by determining packet size, e.g. maximum transfer unit [MTU]
• CPC Class Codes: H04L 47/43 Assembling or disassembling of packets, e.g. segmentation and reassembly [SAR]

Abstract

Network load is reduced by combining packets by considering the MTU of a transmission path. When a routing processing unit detects the transmission of a large number of packets addressed to the same destination network, a routing information gathering unit determines the MTU of a transmission path along which the packets are to be transmitted. A combining unit assembles a combined packet by combining packets up to a length that does not exceed the MTU of the transmission path, and sends out the combined packet.

Claims

1. A network relay apparatus comprising:

a routing information gathering unit for determining the maximum transmission unit of a transmission path along a route over which packets are to be transmitted; and

a combining unit for assembling a combined packet by combining packets up to a length that does not exceed the maximum transmission unit of said transmission path.

2. An apparatus according to

claim 1

, wherein said combined packet carries as a destination address the address of an endpoint of the route over which said packets are transmitted in combined form, said apparatus further comprising:

a disassembling unit for disassembling a received combined packet into individual packets if the destination address of said received combined packet matches the address of said apparatus.

3. An apparatus according to

claim 1

, further comprising a routing processing unit for selecting a path having the largest maximum transmission unit as a path for said combined packet from among a plurality of transmission paths to the same destination.

4. An apparatus according to

claim 3

, wherein said routing processing unit selects a path having the largest maximum transmission unit as a path for said combined packet from among a plurality of transmission paths to the same destination by excluding the path along the shortest route.

5. An apparatus according to

claim 1

, further comprising a combine allow/disallow determining unit for determining, based on a packet attribute, whether or not said combining unit should be made to combine packets.

6. An apparatus according to

claim 1

, further comprising a reassembling unit for disassembling a received combined packet into individual packets and reassembling the same into a combined packet of a length not exceeding the maximum transmission unit of the currently selected path if the length of said received combined packet exceeds said maximum transmission unit.

7. A method of combining packets, comprising the steps of:

determining the maximum transmission unit of a transmission path along a route over which packets are to be transmitted; and

assembling a combined packet by combining packets up to a length that does not exceed the maximum transmission unit of said transmission path.

8. A method according to

claim 7

, wherein said combined packet carries as a destination address the address of an endpoint of the route over which said packets are transmitted in combined form, said method further comprising the step of:

disassembling a received combined packet into individual packets if the destination address of said received combined packet matches the address of an apparatus that received said combined packet.

9. A method according to

claim 7

, further comprising the step of selecting a path having the largest maximum transmission unit as a path for said combined packet from among a plurality of transmission paths to the same destination.

10. A method according to

claim 9

, wherein in said selecting step, a path having the largest maximum transmission unit is selected as a path for said combined packet from among a plurality of transmission paths to the same destination by excluding the path along the shortest route.

11. A method according to

claim 7

, further comprising the step of determining, based on a packet attribute, whether to combine or not combine packets.

12. A method according to

claim 7

, further comprising the step of disassembling a received combined packet into individual packets and reassembling the same into a combined packet of a length not exceeding the maximum transmission unit of the currently selected path if the length of said received combined packet exceeds said maximum transmission unit.