Traffic engineering featuring dynamic lightpath provisioning in multilayer GMPLS optical networks

Abstract

Wavelength-routed networks are viewed as less flexible than IP-routed networks because of the dedicated nature of optical path and incurred optical layer constraints, e.g., wavelength continuity constraints. However, current wavelength-routed networks operating in the WDM environment are empowered with the potential of dynamic and fast provisioning of high-bandwidth optical paths. This potential is currently being addressed by intelligent traffic engineering (TE) on multilayer networks that combine both a broadband optical layer and a grooming-capable electronic layer. We propose a dynamic TE scheme within the framework of multilayer generalized multiprotocol label switching (GMPLS), which takes into consideration the simple nature of an all-optical (OOO) path, the flexibility and grooming efficiency of optical-electrical-optical (OEO) connection, and the support of traffic quality of service (QoS). It optimizes the utilization of OOO and OEO connections in a hybrid fashion through the concept of lightpath tunneling that can adapt to real-time traffic demands. Simulations based on this TE scheme show that the optical transceiver requirement it core nodes can be reduced to only ~20% of that of the IP-routed networks without sacrificing performance. This TE scheme can also be adapted to network scenarios where very limited numbers of transceivers are deployed.