Performance Evaluation of Deflection Routing in Optical IP Packet-Switched Networks

Abstract

In previous papers [5,6], an optical switch architecture was proposed to handle variable-length packets such as IP datagrams, based on an AWG device to route packets and equipped with a fiber delay-line stage as optical input buffer. Unfortunately, extensive simulations of optical networks built with switches of this type showed that considerable buffering capability would be required in order to achieve acceptable performance. In this work, therefore, we studied the effectiveness of packet deflection as a mean for solving packet contentions on outputs of optical switches. Optical transport networks were simulated, evaluating the performance of packet deflection routing, based on a traffic model adherent to real IP traffic measurements. Full-mesh and wheel network topologies have been considered, comparing results to assess deflection effectiveness. Our simulation results show that deflection routing leads to satisfying performance even using buffers with limited size. Furthermore, the average delivery delay does not suffer heavy penalty from packet deflection, even under heavy traffic conditions.