All-optical networks with sparse wavelength conversion

TLDR

Wavelength‑routing networks provide wavelength reuse and scalability, making them suitable for wide‑area networks, and this study examines how topological connectivity and wavelength conversion affect circuit‑switched all‑optical networks. The study aims to analyze how topological connectivity and wavelength conversion influence blocking in circuit‑switched all‑optical networks by proposing an analytical framework for arbitrary topologies. The authors develop a blocking‑analysis framework that models networks with variable numbers of converters, applies it to ring, mesh‑torus, and hypercube topologies, and evaluates the trade‑off between connectivity, conversion, and wavelength availability, including random topologies. Results indicate that a small number of converters can achieve desired performance, but conversion benefits depend on load, wavelength count, and connectivity, with limited advantage in some cases.

Abstract

Unlike broadcast-and-select networks, wavelength-routing networks offer the advantages of wavelength reuse and scalability and are thus suitable for wide-area networks (WANs) We study the effects of topological connectivity and wavelength conversion in circuit-switched all-optical wavelength-routing networks. A blocking analysis of such networks is given. We first propose an analytical framework for accurate analysis of networks with arbitrary topology. We then introduce a model for networks with a variable number of converters and analyze the effect of wavelength converter density on the blocking probability. This framework is applied to three regular network topologies that have varying levels of connectivity: the ring, the mesh-torus, and the hypercube. The results show that either a relatively small number of converters is sufficient for a certain level of performance or that conversion does not offer a significant advantage. The benefits of conversion are largely dependent on the network load, the number of available wavelengths, and the connectivity of the network. Finally, the tradeoff between physical connectivity, wavelength conversion, and the number of available wavelengths is studied through networks with random topologies.