Design and Perfomance Evaluation of Scalable TWIN Networks

TWIN has been introduced as an efficient and cost-effective network architecture that can provide multiple types of services without relying on packet switching or TDM switching in the network core. In the basic TWIN, the maximum number of nodes N in a network is limited by the number of available wavelengths W. In this paper, we propose a scalable TWIN whereby a given color may be reused on multiple destinations, thereby allowing N > W. Given a physical topology and a traffic matrix, we propose an effective approach that assigns W colors to N destinations and designs a multipoint-to-point tree for each destination to construct a virtual topology. We evaluate the performance of our approach using the single-hop throughput and a multi- hop congestion measure. The performance results reveal both the effectiveness of our approach compared to an upper bound and the robustness of the virtual topology in the face of changing traffic patterns.