Design and analysis of a bufferless Optical Packet Switch architecture with Wavelength Optical Crossbars

Optical Packet Switching (OPS) is a promising technology to enable next-generation high-speed IP networks. In OPS networks, contention may arise when two or more packets need to be directed to the same output port, leading to packet loss, and thus lower switching performance. Traditional OPS architectures use two techniques to resolve the contention, namely, optical buffering using Fiber Delay Lines (FDLs) and conversion using Wavelength Converters (WCs). The use of FLDs and WCs may enhance performance but at an increased hardware complexity. Thus, reducing complexity without impacting the overall switching performance is an important design issue in OPS architectures. Accordingly, in this paper, we propose a bufferless OPS architecture by adopting Wavelength Optical Crossbars (WOCs) that can combine both switching and wavelength conversion capability. The new architecture aims at improving the Packet Loss Probability (PLP) while reducing the overall conversion and switching complexity compared to conventional architectures. Analysis of the proposed architecture confirms that, for the same PLP, a reduction in conversion complexity by more than 80% while using around 2% of the switches compared to conventional architectures.