An Autonomic Virtual Topology Design and Two-Stage Scheduling Algorithm for Light-Trail WDM Networks

Light-trails (LTs) have been proposed as a solution for optical networking to provide support for emerging services such as video-on-demand, pseudo-wires, data-centers, etc. To provision these services we require features such as dynamic bandwidth provisioning, optical multicasting, sub-wavelength grooming and a low-cost hardware platform-all of which are available through the LT concept. Architectural, performance, resilience and implementation studies of LTs have led to consideration of this technology in metropolitan networks. In the area of architecture and performance, significant literature is available in terms of static network optimization. An area that has not yet been considered and which is of service provider importance (from an implementation perspective) is the stochastic behavior and dynamic growth of the LT virtual topology. In this paper, we propose a two-stage scheduling algorithm that efficiently allocates bandwidth to nodes within a LT and also grows the virtual topology of LTs based on basic utility theory. The algorithm facilitates growth of the LT topology fathoming across all the necessary and sufficient parameters. The algorithm is formally stated, analyzed using Markov models and verified through simulations, resulting in 45% betterment over existing linear program (LP) or heuristic models. The outcome of the growth algorithm is an autonomic optical network that suffices for service provider needs while lowering operational and capital costs. This paper presents the first work in the area of dual topology planning-at the level of connections as well as at the level of the network itself.