Path selection with tunnel allocation in the optical Internet based on generalized MPLS architecture

GMPLS was devised to be able to support multi-granularity traffic and bundling of wavelength channels in the optical domain. It has been a challenge to achieve an efficient and flexible use of the multi-granularity OXCs (MG-OXCs) in the optical next generation Internet which is assumed to deploy a generalized MPLS (GMPLS) based control plane. In this paper, a heuristic algorithm, capacity-balanced static tunnel allocation (CB-STA), is proposed for solving the problem of routing and wavelength assignment with tunneling (RWAT), which is aimed at facilitating an efficient use of bandwidth in the WDM networks with MG-OXCs. CB-STA allocates fiber and waveband tunnels into networks at the network planning stage, which requires each tunnel to have a fixed length and capacity-balanced characteristics, in order to increase the link utilization in the fiber and waveband switching layers. A comparison is made, using simulation, between CB-STA and a dynamic tunnel allocation scheme. Detailed discussions are provided.