Patent · US Expired

Multi-frame transmission control for token ring networks

US4964113A · kind A · utility

20Cited by
4References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 20, 1989
Grant dateOct 16, 1990
Priority date
Expiry dateOct 20, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L12/433
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for enabling the transmitter to decide the number of variable length frames that can be trasmitted within the token holding timer (THT) window. The last frame decision algorithm enables the transmitter to set the intermediate frame bit in the ending delimiter to the right state to indicate the status of each frame in the transmitted frame sequence. A look-ahead technique is used to check the remaining transmit time available in the THT time window, therefor, no ring bandwidth is wasted on partially transmitted aborated frames, effectively optimizing the throughput of the network. Since key variables in the last frame decision algoritm are softwar programmable, the algorithm is independent of ring speed. The algorithm counts transmitted octets instead of measuring transmission time in deciding whether to transmit an additional frame. The algorithm can be applied to either signal frame or multi-frame transmit mode and to either normal or early token release. It is applicable to both the IEEE 802.5 local area network standard for token ring networks and the AnSI X3T9.5 standard for FDDI.

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