Accession Number:

ADA459702

Title:

Collision Avoidance and Resolution Multiple Access with Transmission Groups

Descriptive Note:

Research paper

Corporate Author:

CALIFORNIA UNIV SANTA CRUZ DEPT OF COMPUTER ENGINEERING

Report Date:

1997-01-01

Pagination or Media Count:

10.0

Abstract:

The Collision Avoidance and Resolution Multiple Access protocol with nonpersistent trees and transmission groups CARMA-NTG is presented and analyzed. CARMA-NTG dynamically divides the channel into cycles of variable length each cycle consists of a contention period and a group-transmission period. During the contention period, a station with one or more packets to send competes for the right to be added to the group of stations allowed to transmit data without collisions. This is done using a collision resolution splitting algorithm based on a request-to-sendclear-to-send RTSCTS message exchange with non-persistent carrier sensing. CARMA-NTG ensures that one station is added to the group transmission period if one or more stations send requests to be added in the previous contention period. The group-transmission period is a variable-length train of packets that are transmitted by stations that have been added to the group by successfully completing an RTSCTS message exchange in previous contention periods. As long as a station maintains its position in the group, it is able to transmit data packets without collision. An upper bound is derived for the average costs of obtaining the first success in the splitting algorithm. This bound is then applied to the computation of the average channel utilization in a fully connected network with a large number of stations. These results indicate that collision resolution is a powerful mechanism in combination with floor acquisition and group allocation multiple access.

Subject Categories:

  • Computer Systems
  • Computer Systems Management and Standards
  • Telemetry
  • Radio Communications

Distribution Statement:

APPROVED FOR PUBLIC RELEASE