Routing and Wavelength Assignment (RWA): Overview

Abstract

Routing and wavelength assignment (RWA) constitutes one of the most fundamental elements in the control and management of an optical network. This chapter provides an introduction to the design principles and objectives of the constraint of the RWA problem, and an overview of proposed schemes and approaches of the implementation and analytical modeling of the RWA process. The constraints imposed on a wavelength-routed optical network are outlined in Section 3.2, which includes topics of physical constraint and diversity constraint. Section 3.3 describes modeling of optical networks with and without wavelength conversion capability. The model incorporates networks containing partial wavelength convertible nodes with different conversion ranges. We also provide an algorithm for performing optimal routing and wavelength assignment in networks with nodes of partial wavelength conversion capability. The approach is based on a modified Dijkstra’s shortest path first algorithm, and can achieve a good computation complexity compared with some other reported schemes.