Communication system and method utilizing request-reply communication patterns for data compression

• US 6,963,587 B2
• Filed: 03/21/2001
• Issued: 11/08/2005
• Est. Priority Date: 11/16/2000
• Status: Expired due to Term

• Current Assignee: Unwired Planet LLC (JP Morgan Chase & Co)
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Christoffersson, Jan, Hannu, Hans, Svanbro, Krister
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): JONES, PRENELL P
• Application Number:
  US09/814,407
• Publication Number:
  US 20020057715A1
• Time in Patent Office: 1,693 Days
• Field of Search: 370/477, 370/238, 370/310, 370/474, 370389-395, 370/516, 370/521, 709/247, 709200-211, 341/106, 341/51, 341 60- 65, 341/87, 375/240, 455/72
• 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: H04L 1/1657 Implicit acknowledgement of correct or incorrect reception, e.g. with a moving window
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 69/04 Protocols for data compression, e.g. ROHC

Abstract

A method, system, and apparatus for increasing the efficiency and robustness of the compression of a communication protocol for communication between entities over bandwidth limited communication links. The present invention uses the request-reply nature of communication protocols to update compression and decompression dictionaries. Each communication entity will update its dictionary with a new message as soon as it is known that the other communication entity has access to the message. In one aspect of the present invention, an entity updates a compression/decompression dictionary by updating the dictionary with sent messages as soon as a reply arrives from the other entity, and by updating the dictionary with received messages immediately. In another aspect of the present invention, received messages are used to update an entity'"'"'s decompression dictionary and sent messages are used to update an entity'"'"'s compression dictionary.

Claims

1. A method of facilitating compressed message communication between a first communication entity and a second communication entity, said method comprising the steps of:

compressing, at said first communication entity, a portion of a first communication message using a first dictionary to produce a first compressed communication message;

transmitting said first compressed communication message to said second communication entity;

receiving said first compressed communication message at said second communication entity;

decompressing, at said second communication entity, said first compressed communication message using a second dictionary to reproduce said first communication message;

adding said portion of said first communication message to said second dictionary;

compressing, at said second communication entity, a portion of a second communication message using said second dictionary to produce a second compressed communication message;

transmitting said second compressed communication message to said first communication entity;

receiving said second compressed communication message at said first communication entity;

in response to receiving said second compressed communication message, adding said portion of said first communication message to said first dictionary; and

decompressing, at said first communication entity, said second compressed communication message using said first dictionary to reproduce said second communication message; and

adding said portion of said second communication message to said first dictionary.

2. The method of claim 1, wherein said step of transmitting said first compressed communication message and said step of transmitting said second compressed communication message comprises transmitting over a wireless interface.

3. The method of claim 1, said method further comprising the steps of:

compressing, at said first communication entity, a portion of a third communication message using said first dictionary to produce a third compressed communication message;

transmitting said third compressed communication message to said second communication entity;

receiving said third compressed communication message at said second communication entity;

in response to receiving said third compressed communication message, adding said portion of said second communication message to said second dictionary; and

decompressing, at said second communication entity, said third compressed communication message using said second dictionary to reproduce said third communication message.

4. A method of facilitating compressed message communication between a first communication entity and a second communication entity, said method comprising the steps of:

compressing, at said first communication entity, a portion of a first communication message using a first dictionary to produce a first compressed communication message;

transmitting said first compressed communication message to said second communication entity;

receiving said first compressed communication message at said second communication entity;

decompressing, at said second communication entity, said first compressed communication message using a second dictionary to reproduce said first communication message;

adding said portion of said first communication message to said second dictionary, compressing, at said second communication entity, a portion of a second communication message using a third dictionary to produce a second compressed communication message;

transmitting said second compressed communication message to said first communication entity;

receiving said second compressed communication message at said first communication entity;

adding said portion of said first communication message to said first dictionary;

decompressing, at said first communication entity, said second compressed communication message using a fourth dictionary to reproduce said second communication message; and

adding said portion of said second communication message to said fourth dictionary.

5. A communication device, comprising:

a receiver unit;

a transmitter unit;

a processor; and

memory having stored therein at least one dictionary and program software having instructions which, when executed by the processor, causes the communication device to;

compress, using at least one dictionary, a portion of a communication message to obtain a compressed portion thereof;

transmit by said transmitter, unit, said communication message having the compressed portion to a second communication device; and

add the portion of said communication message which was previously compressed to said at least one dictionary after receiving a reply communication message sent by the second communication device to said receiver unit.

6. The communication device of claim 5, wherein said at least one dictionary comprises a first dictionary for storing said portion of the communication message and a second dictionary for storing at least one portion of the reply communication message received by said receiver unit.

7. The communication device of claim 5, wherein said communication device comprises a mobile terminal.

8. The communications device of claim 5, wherein said communication device comprises a SIP communication node.

9. The communications device of claim 5, wherein said another communications device comprises a mobile terminal.

10. The communications device of claim 5, wherein said another communications device comprises a SIP communication node.

11. A communication system for facilitating compressed message communication, said communication system comprising:

a first communication entity for sending a first communication message, said first communication entity comprising;

a first receiving means;

a first dictionary;

a first compressor, in communication with said first dictionary, said first compressor using said first dictionary to compress a portion of a first communication message to produce a first compressed communication message;

a first transmitting means, in communication with said first compressor, for transmitting said first compressed communication message to a second communication entity;

a first decompressor;

a first updating means, in communication with said first decompressor and said first dictionary, for adding said portion of said first communication message to said first dictionary after said first communication entity receives a reply message sent by the second communication entity in response to receiving the first compressed communication message; and

said second communication entity comprising;

a second receiving means for receiving said first compressed communication message;

a second dictionary;

a second decompressor, in communication with said second receiving means and said second dictionary, for decompressing said first compressed communication message using said second dictionary to reproduce said first communication message; and

a second updating means, in communication with said second decompressor and said second dictionary, for updating said portion of said first communication message to said second dictionary.

12. The communication system of claim 11, said second communication entity further comprising:

a second compressor, in communication with said second dictionary, for compressing a portion of a second communication message using said second dictionary to produce a second compressed communication message; and

a second transmitting means, in communication with said second compressor, for transmitting said second compressed communication message to said first communication entity.

13. The communication system of claim 12, said first communication entity further comprising:

said first receiving means for receiving said second compressed communication message; and

said first decompressor, in communication with said first receiving means and said first dictionary, for decompressing said second compressed communication message using said first dictionary to reproduce said second communication message.