CHAINED CHECKSUM ERROR CORRECTION MECHANISM TO IMPROVE TCP PERFORMANCE OVER NETWORK WITH WIRELESS LINKS

• US 20130042162A1
• Filed: 10/15/2012
• Published: 02/14/2013
• Est. Priority Date: 09/02/2008
• Status: Active Grant

• Current Assignee: ANNA University, KBC Research Foundation Pvt Ltd.
• Original Assignee: ANNA University, KBC Research Foundation Pvt Ltd.
• Inventors: Muthu, Sethuraman
• Granted Patent: US 8,527,852 B2
• Time in Patent Office: Days
• US Class Current: 714/755
• CPC Class Codes: H03M 13/09 Error detection only, e.g. using cyclic redundancy check [CRC] codes or single parity bit
• CPC Class Codes: H03M 13/6547 TCP, UDP, IP and associated protocols, e.g. RTP
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 1/008 where the control data relates to payload of a different packet
• CPC Class Codes: H04L 1/0083 Formatting with frames or packets; Protocol or part of protocol for error control
• CPC Class Codes: H04L 1/0088 in control part
• 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 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06
• CPC Class Codes: H04W 80/06 Transport layer protocols, e.g. TCP [Transport Control Protocol] over wireless transmission control protocol/Internet protocol [TCP/IP] or user datagram protocol [UDP] H04L69/16

Abstract

Data communication, with improved error detection, of a signal having a plurality of data blocks, by: error checking a received data block in a first sequence using a first polynomial, beginning with a first predetermined initial error checking state, producing a first CSUM; error checking the received data block in a second sequence using a second polynomial, using the first CSUM as a second predetermined initial error checking state, producing a second CSUM; comparing the second CSUM to the first predetermined initial error checking state to detect errors in the data communication; and repeating the above steps for sequential data blocks of the data communication, wherein the first polynomial is an inverse of the second polynomial.

Claims

1. A method of receiving a data communication comprising a plurality of data blocks over a network including at least one wireless link, the method comprising:

error checking a received data block in a first sequence beginning with a first predetermined initial error checking state to produce a first checksum, the error checking being performed using a first error checker;

error checking the received data block in a second sequence using the first checksum as a second predetermined initial error checking state to produce a second checksum; and

comparing the second checksum to the first predetermined initial error checking state to detect errors in the data communication.

2. The method of claim 1, wherein the error checking the received data block in the first sequence is performed using a first polynomial.

3. The method of claim 2, wherein the error checking the received data block in the second sequence is performed using a second polynomial.

4. The method of claim 3, wherein the first polynomial is an inverse of the second polynomial.

5. The method of claim 3, wherein the first polynomial comprises 1+x⁶+x⁷ and the second polynomial comprises 1+x+x⁷.

6. The method of claim 1, wherein the second sequence is in the opposite direction of the first sequence.

7. The method of claim 1, further comprising deriving the first predetermined initial error checking state from a previously received data block.

8. The method of claim 1, wherein the data communication is performed using a transmission control protocol.

9. A method of receiving a data communication comprising a plurality of data blocks over a network including at least one wireless link, the method comprising:

error checking a first received data block in a first sequence beginning with a first predetermined initial error checking state to produce a first checksum, the error checking being performed using a first error checker;

error checking a second received data block in the first sequence beginning with the first checksum to produce a second checksum, the second received data block received after the first received data block;

error checking the second received data block in a second sequence beginning with the second checksum to produce a third checksum; and

comparing the third checksum to the first checksum to detect errors in the data communication.

10. The method of claim 9, wherein when the third checksum equals the first checksum the first received data block, the second received data block, and the second checksum include no errors.

11. The method of claim 9, further comprising deriving the first predetermined initial error checking state from a previously received data block.

12. The method of claim 9, wherein the second sequence is in the opposite direction of the first sequence.

13. The method of claim 9, wherein no data block is received between the first received data block and the second received data block.

14. The method of claim 9, wherein the first sequence is performed using a first polynomial and the second sequence is performed using a second polynomial, the second polynomial being an inverse of the first polynomial.

15. The method of claim 9, further comprising comparing the first checksum with a received checksum associated with the first received data block.

16. A method of receiving a data communication comprising a plurality of data blocks over a network including at least one wireless link, the method comprising:

receiving a data block where a first chained checksum for the data block is chained to a second chained checksum for a previously received data block;

computing an independent checksum for the data block using the second chained checksum and the data block, the independent checksum being unchained from the second chained checksum; and

detecting errors in the data block based on the independent checksum.

17. The method of claim 16, wherein computing an independent checksum for the data block comprises:

computing a first temporary checksum using a zero data block with values of zero in a first sequence beginning with the second chained checksum;

computing a second temporary checksum using the data block in the first sequence beginning with a zero checksum with values of zero;

adding the first temporary checksum and the second temporary checksum to compute the independent checksum.

18. The method of claim 17, wherein the first temporary checksum and the second temporary checksum are computed using a first polynomial.

19. The method of claim 18, wherein the first chained checksum is computed using the data block in a first sequence beginning with the second chained checksum using the first polynomial.

20. The method of claim 16, wherein the first chained checksum is computed using the data block in a first sequence beginning with the second chained checksum.