ANALYTICAL MODEL AND PERFORMANCE ANALYSIS OF SHARED BUFFER ATM SWITCHES UNDER NONUNIFORM TRAFFIC

For uniform traffic, ATM switches employing shared buffering have lowe r cell loss probability and better buffer utilization than other buffe ring strategies. However, the performance of shared-buffer switches de grades dramatically under non-uniform traffic. Traffic nonuniformity i s inherent in telecommunications, and is likely to be present in ATM n etworks because of the different characteristics of traffic sources su ch as video, voice and data. A number of buffer management schemes whi ch are designed to overcome the adverse effect of non-uniform traffic in shared-buffer ATM switches have been proposed and studied. In this paper, we analyse the pushout technique to purge hot-spot cells which unfairly occupy the buffer. We call it Hot-Spot Pushout (HSPO). We dev elop an analytical model for buffer sharing with and without HSPO unde r non-uniform traffic and validate it using simulation. We also simula te other buffer sharing schemes available in the literature and show t hat HSPO performs consistently better than all of them in the presence of non-uniform traffic.