Analysis of Shared Bu er Multistage Networks with Hot Spot

Multistage Interconnection Networks based on shared buuering are known to have better performance and buuer utilization than input or output buuered switches. Shared buuer switches do not suuer from head of line blocking which is a common problem in simple input buuering. Shared buuer switches have previously been studied under uniform and unbalanced traac patterns. However, due to the complexity of the model, the performance of such a network, in the presence of a single hot spot, has not been fully explored. A hot spot arises when one of the outputs of the network becomes very popular. In this paper, we develop a model for a multistage interconnection network constructed from shared buuer switching elements and operating under a hot spot traac pattern. The model is validated by comparison with simulation results. The model is used to study the network performance in terms of the through-put, packet delay, packet loss probability and the optimal buuer utilization. Numerical results show that, in the presence of hot spot traac, shared buuer switches degrade more signiicantly than switches with dedicated input and/or output buuers.