Enhancing Bandwidth on Demand Service Based on Virtual Network Topology Control

This paper presents multilayer IP optical traffic engineering technologies based on VNT (virtual network topology) control and studies their application to BoD (bandwidth on demand) services to improve flexibility and efficiency. Multilayer TE (traffic engineering) optimizes network-resource utilization considering all layers, rather than performing optimization independently for each layer, by performing traffic control in cooperation with IP routes and optical cross-connects (OXCs) in multilayer IP optical networks. Hence, we can accommodate unexpected traffic- demand fluctuations and network failures by dynamically reconfiguring VNT so that it consists of several optical paths among IP routers. The key to achieving multilayer TE lies in the optimal design of VNT based on measured traffic demand. Thus, by introducing multilayer TE into a BoD service, we can enhance flexibility of the service regarding unexpected traffic- demand changes without adding operational overhead that affects customers of the service.