Reduced load approximations for large-scale optical WDM networks offering multiclass services

Abstract

We propose an approximation method for performance analysis of large-scale optical WDM networks (comprising multiple interconnected optical WDM networks) that offer multiclass services. In such networks, lightpaths are dynamically set up and terminated between source and destination nodes in order to serve calls in various service classes, and these lightpaths traverse through a number of interconnected optical WDM networks that may be in different administrative domains. Each service class is characterized by its resource requirements (number of wavelengths needed for a call) and expected call holding time (or subscription period). We model the large-scale optical network as a two-level hierarchical multiclass loss network; the lower level of hierarchy consists of individual optical WDM networks (network segments). Each network segment is abstracted to a logical node at the higher level of hierarchy, and these logical nodes are connected through logical links. Then, we present a methodology of approximately computing per class end-to-end approximate blocking probabilities.