Performance Analysis of Traffic-Groomed Optical Networks Employing Alternate Routing Techniques

Recent advances in telecommunication networks have allowed WDM to emerge as a viable solution to the ever-increasing demands of the Internet. In a wavelength-routed optical network, traffic is transported over lightpaths, which exclusively occupy an entire wavelength on each hop of the source-destination path. Because these networks carry large amounts of traffic, alternate routing methods are designed in order to allow traffic to be properly re-routed from source to destination in the event of certain events, such as link blocking or failure. In this paper, we consider a tandem traffic-groomed optical network, modeled as a multi-level overflow system, where each level represents a wavelength between adjacent nodes. The queueing network is analyzed using a combination of methods. As will be shown, the decomposition method provides a good approximate analysis of large overflow systems supporting traffic from multiple sources.