Multi-Channel Token Ring, Introduction and Throughput Analysis

Abstract

If traffic on a large LAN segment can be localized, increased user throughput can be achieved by dividing the LAN segment into smaller interconnected segments. Each localized segment contains a group of communicating stations. If traffic cannot be localized, increasing the data-rate of the LAN is the typical solution to providing increased user bandwidth. An alternative solution is architecting multiple parallel LANs to increase bandwidth. This paper proposes a technique for increasing the bandwidth of a LAN without changing the data rate; namely, by utilizing a number of independent channels operating in parallel and at the same data rate. This technique is applied to token ring and is named Multi-Channel Token Ring (MCTR). Driving forces for MCTR are; preserving existing hardware and software as much as possible, being IEEE 802.5 standards compliant, and offering increased reliability. MCTR can be implemented without changing work-station interfaces or LAN protocols. A means of precisely computing peak single station throughput on a token ring LAN is developed. This throughput analysis is then applied to MCTR.