Efficient automatic repeat request method using variable length sequence numbers
US6654422B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 1999 |
| Grant date | Nov 25, 2003 |
| Priority date | — |
| Expiry date | May 14, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/1809
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A variable length sequence number is used to identify data units in a communication channel. The sequence number associated with the most recent data that has been received successfully and the sequence number expected with the next new data message to be received are examined to determine the minimum size sequence number necessary to unambiguously identify to the transmitter incorrectly received data that must be retransmitted in a later message. The receiver provides the transmitter with the sequence number associated with the last successfully received byte of data and the sequence number associated with the next expected byte of data. The receiver communicates this information to the transmitter using a NAK control message. The transmitter then uses the sequence number of the next byte of data to be transmitted and the information received in the control message from the receiver to determine the smallest number of bits necessary to represent the sequence numbers for both data transmissions and the retransmission of data that was not received properly by the receiver.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.