Communication system and method for shared context compression

• US 6,950,445 B2
• Filed: 03/21/2001
• Issued: 09/27/2005
• Est. Priority Date: 11/16/2000
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Svanbro, Krister, Allden, Johan
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): JONES, PRENELL P
• Application Number:
  US09/814,434
• Publication Number:
  US 20020057716A1
• Time in Patent Office: 1,651 Days
• Field of Search: 370/477, 370/474, 370/238, 370/310, 370/516, 370/521, 709/247, 709200-211, 341/106, 341/51, 341 60- 65, 341/87
• US Class Current: 370/477
• CPC Class Codes: H03M 7/30 Compression speech analysis-synthesis for redundancy reduction G10L19/00; for image communication H04N; Expansion; Suppression of unnecessary data, e.g. redundancy reduction
• CPC Class Codes: H03M 7/3079 Context modeling
• CPC Class Codes: H03M 7/6052 Synchronisation of encoder and decoder
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365

Abstract

A system, method, and apparatus for increasing the efficiency of the compression of a communication protocol for use over bandwidth limited communication links. One aspect of the present invention provides for the sharing of context information between a compressor and decompressor at each communication entity in a communication system. As a result, context information will be shared for each channel pair. In another aspect of the present invention, multiple communication sessions between communication entities may share the same context information for the compression and decompression of communication messages.

Claims

1. A communication entity for facilitating compressed message communication, said communication entity comprising:

a context table containing context information associated with at least one communication message;

a compressor, in communication with said context table, said compressor using said context information to compress at least one transmitted communication message;

a decompressor, in communication with said context table, said decompressor using said context information to decompress at least one received communication message; and

said compressor and said decompressor both share said context table and both update said context table using context information within said at least one transmitted communication message and said at least one received communication message.

2. The communication entity of claim 1, wherein said context information comprises at least a portion of at least one information field of said at least one communication message.

3. The communication entity of claim 2, wherein said at least a portion of said at least one information field comprises at least one header field.

4. The communication entity of claim 3, wherein said at least one header field comprises at least one Internet Protocol header field.

5. The communication entity of claim 1, wherein said context information comprises a dictionary.

6. The communication entity of claim 1, wherein said at least one transmitted communication message is transmitted using a first communication channel and said at least one received communication message is received over a second communication channel, said first communication channel and said second communication channel comprising a channel pair.

7. The communication entity of claim 1, wherein said communication entity comprises a mobile terminal.

8. The communication entity of claim 1, wherein said communication entity comprises a communication node.

9. The communication entity of claim 1, wherein said at least one transmitted communication message is compressed using a first context, and said at least one received communication message is decompressed using a second context.

10. The communication entity of claim 9, wherein said first context is substantially the same as said second context.

23. The communication entity of claim 1, wherein said context information is used to enable both header compression and signaling compression.

24. The communication entity of claim 1, wherein said context information comprises a header compression context.

25. The communication entity of claim 1, wherein said context information comprises a signaling compression dictionary.

26. The communication entity of claim 2, wherein said at least one header field comprises a fixed size header field.

27. The communication entity of claim 2, wherein said at least one header field comprises a variable size header field.

11. A method for enabling a communication entity to facilitate compressed message communication, said method comprising the steps of:

maintaining a context table containing context information associated with at least one communication message;

compressing at least one transmitted communication message using said context information;

decompressing at least one received communication message using said context information; and

updating said context table using context information in said at least one transmitted communication message and said at least one received communication message.

12. The method of claim 11, wherein said context information comprises at least one information field of said at least one communication message.

13. The method of claim 12, wherein said at least one information field comprises at least one header field.

14. The method of claim 13, wherein said at least one header field comprises at least one Internet Protocol header field.

15. The method of claim 11, wherein said context information comprises a dictionary.

16. A method for enabling a communication entity to facilitate compressor message communication, said method comprising the steps of:

compressing a first communication message having first context information to produce a first compressed message;

storing said first context information in a context table;

transmitting said first compressed message over a first communication channel;

receiving a second compressed message over a second communication channel;

decompressing said second compressed message to preduce a second communication message having second context information; and

storing said second context information in said context table, wherein said context table is updated by using said first context information and said second context information respectively associated with said first compressed message and said second compressed message.

17. The method of claim 16, wherein said first communication channel and said second communication channel comprising a channel pair.

18. The method of claim 16, wherein at least one of said first context information and said second context information comprises at least one information field of an Internet Protocol.

19. The method of claim 18, wherein said at least one information field comprises at least one header field.

20. The method of claim 16, wherein at least one of said first context information and said second context information forms an entry in a dictionary.

21. A method for enabling a first communication entity to facilitate multiple compressed message communication session with a second communication entity, wherein said first communication entity performs the following steps:

maintaining a first context table containing context information associated with at least one communication message;

compressing and transmitting a first communication message using the first context table;

compressing and transmitting a second communication message using the first context table;

receiving and decompressing a third communication message using the first context table;

receiving and decompressing a fourth communication message using the first context table; and

updating the first context table using context information in the first, second third and fourth communication messages.

22. The method of claim 21, wherein said second communication entity performs the following steps:

maintaining a second context table containing context information associated with the at least one cummunication meassage;

receiving and decompressing the first communication message using the second context table;

receiving and decompressing the second communication message using the second context table;

compressing and transmitting the third communication message using the second context table;

compressing and transmitting the fourth communication message using the second context table; and

updating the second context table using context information in the first second third and fourth communication message.