Hyper-cluster: a scalable and reconfigurable wide-area lightwave network architecture

This paper presents a network architecture called hyper-cluster employing wavelength-routing, multi-hop packet switching and optical reconfiguration. It is modularly scalable to very large configurations on both hardware and operational bases. A hyper-cluster uses a logical hierarchy for the purpose of addressing but guarantees that all access nodes have a constant number of transceivers. It is a cluster of regular graphs; the clustering structure follows the traffic distribution in a grand granularity. The issue of operational scalability is addressed by presenting a scalable routing protocol. When using shuffle-net as the building block, we also present a novel routing scheme called quantified deflection routing, which improves the call blocking performance significantly. The network throughput and virtual call blocking performance is obtained via simulation on large networks (with size beyond 200 nodes). Numerical results presented by Guo, Acampora and Zhang (see SPIE- The International Society for Optical Engineering, Voice, Video, and Data Communications, Dallas, 1997) show that the dynamic self-routing protocol, combined with quantified deflection routing for the shuffle-net, can achieve excellent resource utilization efficiency for very large networks. When the call arrival rate is below 0.3, the capacity provided by the hyper-cluster dynamic routing algorithm is close to that of an infinite capacity centralized switch (lowest possible call blocking caused exclusively by congestion on the finite capacity user input/output links, never by the switch fabric itself).