Performance Evaluation of Optical Burst Switching Networks

Abstract

Optical Burst Switching (OBS) is a promising switching scheme for wavelength division multiplexing (WDM) networks, which achieves the balance between Optical Packet Switch (OPS) and Optical Circuit Switching (OCS). During the past decade, numbers of papers have studied the performance of OBS. However, most of the analyses in those papers did not consider the existence of self-similarity. Compare with the traffic measurement, the burstiness of Internet traffic has been underestimated in many queuing models, such as Poisson process. This project investigates the performance of TCP over OBS by focusing on the buffer requirement at a bottleneck WDM switch without neglecting the traffic self-similarity. In particular, this project consists of both qualitative and quantitative parts. In the qualitative part, the background about OBS and Long Range Dependency (LRD) traffic has been studied and discussed. In the quantitative part, a two-part analytical model proposed by Wong et al. is used, one open loop model to approximate the packet loss rate at bottleneck and another closed loop model to evaluate the performance with TCP. Based on the analytical model, two simulations are implemented in C++ and ns2 respectively to investigate the buffer requirement in the TCP over OBS.