Robust, inferentially synchronized transmission of compressed transport-layer-protocol headers

• US 20020097722A1
• Filed: 05/03/2001
• Published: 07/25/2002
• Est. Priority Date: 11/16/2000
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Liao, Hong Bin, Zhang, Qian, Zhang, Ya-Qin, Zhu, Wenwu
• Granted Patent: US 7,046,672 B2
• Time in Patent Office: Days
• US Class Current: 370/392
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/193 at the transport layer, e.g. TCP related
• CPC Class Codes: H04L 47/27 Evaluation or update of window size, e.g. using information derived from acknowledged [ACK] packets
• CPC Class Codes: H04L 47/37 Slow start
• CPC Class Codes: H04L 69/04 Protocols for data compression, e.g. ROHC
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/161 Implementation details of TCP/IP or UDP/IP stack architecture; Specification of modified or new header fields
• CPC Class Codes: H04L 69/163 In-band adaptation of TCP data exchange; In-band control procedures
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04L 69/326 in the transport layer [OSI layer 4] H04L69/16 takes precedence

Abstract

An implementation of a technology, described herein, for transmitting compressed network transport-layer-protocol headers in a speedy, efficient, inferentially synchronized, and robust manner. An implementation, described herein, models the transmission of compressed headers to the congestion procedure of the network transport-layer protocol (e.g., TCP'"'"'s). Doing so, the sender of the compressed headers can infer whether the receiver correctly received them. Unlike the slow direct synchronization employed by conventional schemes, this implementation of the present claimed invention inferentially synchronizes by modeling after the congestion procedure of the network transport-layer protocol. This is inherently faster than direct synchronization. Since the implementation performs well over both noiseless and noisy links, it is particularly suited to use over wireless communications channels. This abstract itself is not intended to limit the scope of this patent. The scope of the present invention is pointed out in the appending claims.

Claims

1. A method for efficient transmission of TCP/IP headers via a wireless communications link from a sender to a receiver, the method comprising:

obtaining TCP/IP packets having associated TCP/IP headers;

losslessly compressing the associated headers;

feedback-independently transmitting of a plurality of the compressed headers via the communications link;

the transmitting comprising;

adjusting a sliding window within which the plurality of the compressed headers are transmitted, wherein the adjusting is modeled to react to TCP/IP window-size changes that results from the congestion procedures of TCP/IP;

using the sliding window, W-LSB encoding the plurality of the compressed headers;

sending the resulting W-LSB encoded plurality of compressed headers.

2. A method as recited in claim 1, further comprising inferentially determining whether there is an inconsistent context between the sender and the receiver.

3. A method as recited in claim 1, further comprising:

inferentially determining whether there is an inconsistent context between the sender and the receiver;

if so, then refreshing the context between the sender and the receiver.

4. A method as recited in claim 1, wherein the sender is a header compressor (HC) and the receiver is a header decompressor (HD).

5. A computer comprising one or more computer-readable media having computer-executable instructions that, when executed by the computer, perform the method as recited in claim 1.

6. A computer network comprising a computer comprising one or more computer-readable media having computer-executable instructions that, when executed by the computer, perform the method as recited in claim 1.

7. A computer-readable medium having computer-executable instructions that, when executed by a computer, performs the method as recited in claim 1.

8. A method for efficient transmission of network transport-layer protocol headers via a communications link, the method comprising:

obtaining transport-layer protocol packets having associated transport-layer protocol headers;

compressing the associated headers;

feedback-independently transmitting of a plurality of the compressed headers via the communications link.

9. A method as recited in claim 8, further comprising inferentially determining whether there is an inconsistent context, wherein an inconsistent context is when one or more headers are not properly received by a receiver on the communications link.

10. A method as recited in claim 8, further comprising:

inferentially determining whether there is an inconsistent context, wherein an inconsistent context is when one or more headers are not properly received by a receiver on the communications link;

if so, then refreshing the context to make the context consistent.

11. A method as recited in claim 8, wherein, for the compressing, the headers are compressed losslessly.

12. A method as recited in claim 8, wherein the transmitting comprises:

adjusting a sliding window within which the plurality of the compressed headers are transmitted;

using the sliding window, W-LSB encoding the plurality of the compressed headers;

sending the resulting W-LSB encoded plurality of compressed headers.

13. A method as recited in claim 8, wherein the transmitting comprises:

adjusting a sliding window within which the plurality of the compressed headers are transmitted, wherein the adjusting is modeled to react to window size changes of the transport-layer protocol that results from the congestion procedures of such transport-layer protocol;

using the sliding window, W-LSB encoding the plurality of the compressed headers;

sending the resulting W-LSB encoded plurality of compressed headers.

14. A method as recited in claim 8, wherein the communications link is wireless.

15. A method as recited in claim 8, wherein the network transport-layer protocol is TCP.

16. A computer comprising one or more computer-readable media having computer-executable instructions that, when executed by the computer, perform the method as recited in claim 8.

17. A computer network comprising a computer comprising one or more computer-readable media having computer-executable instructions that, when executed by the computer, perform the method as recited in claim 8.

18. A computer-readable medium having computer-executable instructions that, when executed by a computer, performs the method as recited in claim 8.

20. A method as recited in claim 19 further comprising:

obtaining transport-layer protocol packets having associated transport-layer protocol headers;

compressing the associated headers.

21. A method as recited in claim 20, wherein, for the compressing, the headers are compressed losslessly.

22. A method as recited in claim 19, wherein the synchronizing comprises modeling the encoding upon a congestion procedure of the network transport-layer protocol.

23. A method as recited in claim 19, wherein the synchronizing comprises modeling the size of a sliding window to react to window size changes of the transport-layer protocol that results from congestion procedures of such transport-layer protocol.

24. A method as recited in claim 19 further comprising inferentially determining whether there is an inconsistent context, wherein an inconsistent context is when one or more headers are not properly received by a receiver on the communications link.

25. A method as recited in claim 19 further comprising:

inferentially determining whether there is an inconsistent context, wherein an inconsistent context is when one or more headers are not properly received by a receiver on the communications link;

if so, then refreshing the context to make the context consistent.

26. A method as recited in claim 19, wherein the transmitting comprises:

adjusting a sliding window within which the plurality of the compressed headers are transmitted;

using the sliding window, W-LSB encoding the plurality of the compressed headers;

sending the resulting W-LSB encoded plurality of compressed headers.

27. A method as recited in claim 19, wherein the transmitting comprises:

adjusting a sliding window within which the plurality of the compressed headers are transmitted;

using the sliding window, W-LSB encoding the plurality of the compressed headers;

sending the resulting W-LSB encoded plurality of compressed headers;

the inferential synchronizing comprises modeling the size of the sliding window to react to window size changes of the transport-layer protocol that results as from the congestion procedures of such transport-layer protocol.

28. A method as recited in claim 19, wherein the communications link is wireless.

29. A method as recited in claim 19, wherein the network transport-layer protocol is TCP.

30. A computer comprising one or more computer-readable media having computer-executable instructions that, when executed by the computer, perform the method as recited in claim 19.

31. A computer network comprising a computer comprising one or more computer-readable media having computer-executable instructions that, when executed by the computer, perform the method as recited in claim 19.

32. A computer-readable medium having computer-executable instructions that, when executed by a computer, performs the method as recited in claim 19.

19. A method for efficient transmission of network transport-layer protocol headers via a communications link, the method comprising:

transmitting a plurality of compressed transport-layer protocol headers via the communications link;

inferentially synchronizing.

33. A method for efficient transmission of network transport-layer protocol headers via a communications link, the method comprising:

encoding a plurality of compressed transport-layer protocol headers;

transmitting the plurality of compressed headers via the communications link within a transmission;

inferentially synchronizing such transmission by modeling the encoding upon a congestion procedure of the network transport-layer protocol.

34. A method as recited in claim 33 further comprising:

obtaining transport-layer protocol packets having associated transport-layer protocol headers;

losslessly compressing the associated headers.

35. A method as recited in claim 33, wherein:

the encoding comprises;

adjusting a sliding window within which the plurality of the compressed headers are transmitted;

using the sliding window, W-LSB encoding the plurality of the compressed headers.

36. A method as recited in claim 33, wherein:

the encoding comprises;

adjusting a sliding window within which the plurality of the compressed headers are transmitted;

using the sliding window, W-LSB encoding the plurality of the compressed headers;

the transmitting comprises sending the resulting W-LSB encoded plurality of compressed headers.

37. A method as recited in claim 33, wherein the communications link is wireless.

38. A method as recited in claim 33, wherein the network transport-layer protocol is TCP.

39. A computer-readable medium having computer-executable instructions that, when executed by a computer, performs the method as recited in claim 33.

40. A method for efficient transmission of network transport-layer protocol headers via a communications link, the method comprising:

transmitting a plurality of compressed transport-layer protocol headers via the communications link;

inferentially determining whether there is an inconsistent context, wherein an inconsistent context is when one or more headers are not properly received by a receiver on the communications link;

if so, then refreshing the context to make the context consistent.

41. A method as recited in claim 40, wherein the communications link is wireless.

42. A method as recited in claim 40, wherein the network transport-layer protocol is TCP.

43. A computer-readable medium having computer-executable instructions that, when executed by a computer, performs the method as recited in claim 40.

44. A transmission system comprising:

a transmitter configured to transmit a plurality of compressed transport-layer protocol headers via a communications link to a receiver;

an inferential synchronizer.

45. A system as recited in claim 44, wherein the inferential synchronizer is configured to inferentially determine whether there is an inconsistent context, wherein an inconsistent context is when headers are not properly received by a receiver on the communications link and if so, then refresh the context to make the context consistent.

46. A system as recited in claim 44, wherein the inferential synchronizer is configured to model the size of a sliding window to react to window size changes of the transport-layer protocol that results from congestion procedures of issuch transport-layer protocol.

47. A network computing system comprising a system as recited in claim 44 and a receiver.

48. A system as recited in claim 44, wherein the communications link is wireless.

50. A system as recited in claim 49, wherein the processor is further configured to execute the computer program instructions, which comprises inferentially determining whether there is an inconsistent context, wherein an inconsistent context is when one or more headers are not properly received by a receiver on the communications link.

49. A system for efficient transmission of network transport-layer protocol headers via a communications link, the system comprising:

a memory comprising a set of computer program instructions; and

a processor coupled to the memory, the processor being configured to execute the computer program instructions, which comprise;

obtaining transport-layer protocol packets having associated transport-layer protocol headers;

compressing the associated headers;

feedback-independently transmitting of a plurality of the compressed headers via the communications link.