Patent · US Expired

Error recovery of variable-length packets without sequence numbers or special symbols used for synchronizing transmit retry-buffer pointer

US7248587B1 · kind B1 · utility

18Cited by
7References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 11, 2005
Grant dateJul 24, 2007
Priority date
Expiry dateJan 31, 2026

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L43/0847
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Variable-length packets transmitted over a serial link do not have packet-start fields or unique symbols to mark the beginning of each packet. Instead, a length field indicates the packet's length, allowing the end of the packet to be located. Packets also do not have sequence numbers. When an error is detected, the receiver sends a control symbol over a reverse channel to signal the transmitter. The control symbol never occurs in a normal packet. Packet buffers in the transmitter and receiver have read and write pointers and also have de-allocation pointers that are synchronized between receiver and transmitter. As packets are error checked, the receiver advances its de-allocation pointer and updates the transmitter's de-allocation pointer, allowing the packets to be discarded from the transmitter's buffer only after the receiver finishes error checking. The transmitter re-transmits packets from its buffer starting from the de-allocation pointer when its receives the control symbol.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.