Fast and adaptive packet processing device and method using digest information of input packet

• US 20050030949A1
• Filed: 09/07/2004
• Published: 02/10/2005
• Est. Priority Date: 09/20/1999
• Status: Abandoned Application

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Okamoto, Toshio, Shirakawa, Kenji, Shimojo, Yoshimitsu, Shobatake, Yasuro
• Application Number:
  US10/934,460
• Publication Number:
  US 20050030949A1
• Time in Patent Office: Days
• US Class Current: 370/392
• 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 45/566 Routing instructions carried by the data packet, e.g. active networks
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A packet processing device is formed by a digest information generation unit configured to extract a plurality of prescribed bit sequences from an input packet, and generate a digest information capable of specifying at least a part of a processing to be applied to the input packet, according to values of the plurality of prescribed bit sequences; and a packet processing unit configured to process the input packet using an instruction sequence to be applied to the input packet that is obtained according to the digest information generated by the digest information generation unit, where the digest information generation unit generates the digest information with respect to a next input packet while the packet processing unit carries out a processing for one packet.

Claims

1. A packet processing device, comprising:

a digest information generation unit configured to extract a plurality of prescribed bit sequences from an input packet, and generate a digest information capable of specifying at least a part of a processing to be applied to the input packet, according to values of the plurality of prescribed bit sequences; and

a packet processing unit configured to process the input packet using an instruction sequence to be applied to the input packet that is obtained according to the digest information generated by the digest information generation unit;

wherein the digest information generation unit generates the digest information with respect to a next input packet while the packet processing unit carries out a processing for one packet; and

the digest information generation unit generates the digest information that indicates a packet type by referring to a header portion of the input packet such that the packet type is classified first according to the header portion of the input packet, and then the instruction sequence is generated according to a classified type, so that a number of conditional branches contained in the instruction sequence is reduced.

2. The packet processing device of claim 1, wherein the packet processing unit has a cache and prefetches data into the cache according to the digest information generated by the digest information generation unit.

3. The packet processing device of claim 1, wherein the digest information generation unit has bit patterns for the plurality of prescribed bit sequences corresponding to each digest information, and generates the digest information by comparing values of the plurality of prescribed bit sequences extracted from the input packet with each bit pattern.

4. The packet processing device of claim 1, wherein the digest information generation unit generates the digest information by applying logical calculations for obtaining a prescribed digest information as an output from an input of a bit pattern of the plurality of prescribed bit sequences corresponding to the prescribed digest information, to values of the plurality of prescribed bit sequences extracted from the input packet.

5. The packet processing device of claim 1, wherein the packet processing device includes:

a program memory for storing a plurality of processing routines corresponding to a plurality of digest information; and

a processor for activating and executing one of the plurality of processing routines stored in the program memory that is specified by the digest information generated by the digest information generation unit, using the digest information generated by the digest information generation unit as an interruption signal.

6. The packet processing device of claim 1, wherein the digest information generation unit also extracts parameters other than the digest information for a processing of the input packet from the input packet and gives the parameters along with the digest information to the packet processing unit;

and

the packet processing unit processes the input packet by using the parameters and the instruction sequence obtained according to the digest information.

7. The packet processing device of claim 1, wherein the digest information generation unit stores in advance a plurality of digest information corresponding to a plurality of packet types according to a mixture rate of the packet types in a network to which the packet processing device is connected, and generates a special digest information indicating others when a digest information corresponding to a packet type of the input packet is not stored in advance;

and

the packet processing unit processes the input packet by specifying a packet type in advance when the digest information other than the special digest information is given from the digest information generation unit, whereas the packet processing unit processes the input packet by not specifying a packet type in advance but checking the packet type of the input packet as the input packet is processed, when the special digest information indicating others is given from the digest information generation unit.

8. The packet processing device of claim 1, wherein the packet processing unit caries out a processing for outputting the input packet to a network to which the packet processing device is connected, such that the input packet is transferred to a desired destination.

9. The packet processing device of claim 1, wherein the digest information generation unit gives the digest information that contains additional information generated from a destination information of the input packet, to the packet processing unit;

and

the packet processing unit selects one of a plurality of routing information table search methods according to the additional information, and determines an output path of the input packet by searching through a routing information table using a selected routing information table search method.

10. A packet processing method, comprising the steps of:

(a) extracting a plurality of prescribed bit sequences from an input packet, and generating a digest information capable of specifying at least a part of a processing to be applied to the input packet, according to values of the plurality of prescribed bit sequences; and

(b) processing the input packet using an instruction sequence to be applied to the input packet that is obtained according to the digest information generated by the step (a);

wherein the step (a) generates the digest information with respect to a next input packet while the step (b) carries out a processing for one packet; and

the step (a) generates the digest information that indicates a packet type by referring to a header portion of the input packet such that the packet type is classified first according to the header portion of the input packet, and then the instruction sequence is generated according to a classified type, so that a number of conditional branches contained in the instruction sequence is reduced.

11. The packet processing method of claim 10, wherein the step (b) obtains the instruction sequence by selecting one of a plurality of instruction sequences provided in advance, according to the digest information generated by the step (a).

12. The packet processing method of claim 10, wherein the step (b) obtains the instruction sequence by generating the instruction sequence according to the digest information generated by the step (a).