An Analytical Model for ATM Based Networks Which Utilize Look-Ahead Contention Resolution Switching

Abstract

Interconnection of multiple media sources will be handled by ATM based networks in B-ISDN systems. These ATM networks act as a backbone for subnetworks (such as LANs, MANs, etc). These subnetworks hold individual media or wholly integrated subsets of the necessary data. This paper will present a new analytical model describing the behavior of ATM based interconnection networks which utilize a scheme called Look-Ahead Contention Resolution (LCR). to reduce packet collision and thereby increase throughput. To the knowledge of the authors, this is the only analytical model in the current literature that addresses the LCR. problem. The switches modeled in this work are output queued and are non-lossy. The analytical model gives a set of closed-form equations which lead to an iterative solution for normalized bandwidth and normalized delay for networks in which the queues are searched to a depth of k. (DOS = k.) where 1 ≤ k ≤ sizeof(queue). in order to find a successful candidate for packet transmission during a network cycle. The model provides results which are very accurate compared to simulation results even under very high loads.