System and method for providing transformation of multi-protocol packets in a data stream

• US 7,539,195 B2
• Filed: 09/12/2005
• Issued: 05/26/2009
• Est. Priority Date: 05/04/2001
• Status: Expired due to Fees

• Current Assignee: RPX Corporation
• Original Assignee: SLT Logic LLC
• Inventors: Sarkinen, Scott A., Trivedi, Hemant Vrajlal, Paatela, Jeremy B.
• Primary Examiner(s): Ho, Duc C
• Application Number:
  US11/224,692
• Publication Number:
  US 20060209840A1
• Time in Patent Office: 1,352 Days
• Field of Search: None
• US Class Current: 370/392
• CPC Class Codes: H04J 2203/0082 Interaction of SDH with non-ATM protocols
• CPC Class Codes: H04L 69/08 Protocols for interworking; Protocol conversion
• CPC Class Codes: H04L 69/12 Protocol engines
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A system and method for facilitating packet transformation of multi-protocol, multi-flow, streaming data. Packet portions subject to change are temporarily stored, and acted upon through processing of protocol-dependent instructions, resulting in a protocol-dependent modification of the temporarily stored packet information. Validity tags are associated with different segments of the temporarily-stored packet, where the state of each tag determines whether its corresponding packet segment will form part of the resulting modified packet. Only those packet segments identified as being part of the resulting modified packet are reassembled prior to dispatch of the packet.

Claims

1. A method for multi-protocol packet transfer over a communication network comprising:

receiving at an ingress port, a first packet of information transferred over the communication network from a source using a first layered transmission protocol, the information segmented into a data portion and an ingress header portion in accordance with the first layered transmission protocol;

resolving each layer associated with the first layered transmission protocol to obtain an identity of the first layered transmission protocol;

fetching a set of parsing instructions from a first instruction memory beginning at a location indicated by the identity of the first layered transmission protocol;

executing the set of parsing instructions to extract segments of a search key from the information;

building a search key by assembling the search key segments and applying the search key to a content-addressable-memory to obtain a classification of the information into a plurality of flows;

enforcing a policing function on each of the plurality of flows based upon pre-defined policing criteria associated with said each of said plurality of flows;

based upon the classification, fetching a set of editing instructions from a second instruction memory;

applying the editing instructions to the information to generate an intermediate egress header portion;

manipulating the intermediate egress header portion in response to the policing function enforced on the flow associated with the information to build the egress header portion compliant with a second layered transmission protocol;

assembling a second packet of information from the data portion and the egress header portion; and

transmitting the second packet of information towards a destination through an egress port of a switch fabric using the second layered transmission protocol.

2. The method of claim 1 wherein the parsing instructions are programmatically alterable.

3. The method of claim 1 wherein the policing criteria is programmatically alterable.

4. The method of claim 1 wherein the editing instructions are programmatically alterable.

5. The method of claim 1 wherein the first packet of information includes at least one embedded header associated with a third layered transmission protocol different than the first and second layered transmission protocols and wherein at least a part of the egress header portion is associated with a fourth layered transmission protocol representing a modification of one or more of the first, second and third layered transmission protocols.

6. The method of claim 1 wherein the first packet of information includes at least one embedded header associated with a third layered transmission protocol different than the first and second layered transmission protocols and wherein at least a part of the egress header portion is associated with a fourth layered transmission protocol obtained by modifying at least one of the first, second and third layered transmission protocols.

7. The method of claim 6 wherein the modifying step includes one or more steps of altering the first packet of information, inserting new information in the first packet of information, deleting a portion of the first packet of information, and transforming the first packet of information.

8. The method of claim 1 wherein the step of assembling the second packet of information is completed concurrent with receiving a next packet of information transferred over the communication network at the ingress port.

9. The method of claim 8 wherein the packets of information are received at the ingress port at a rate upwards of 10 Gigabits per second.