Network profit optimization for traffic grooming in WDM networks with wavelength converters

The traffic grooming technique provides a two-layer traffic engineering capability by aggregating and routing up-layer low-bandwidth traffic flows over low-layer re-configurable routed high-bandwidth connections. In this paper, we optimize traffic grooming for static traffic in mesh Wavelength Division Multiplexing (WDM) networks with wavelength converters. The optimization objective is to maximize network profit, which is the difference between resource cost and the revenue generated (by selecting profitable traffic flows). A constrained integer linear programming formulation is given, and a decomposition using Lagrangian relaxation is proposed. We then present a systematic approach to solve this problem and to obtain a performance bound for an arbitrary topology mesh network. Our approach can select traffic flows based on their profit, while obtaining their data path routing, lightpath routing and wavelength assignment at the same time. Our performance evaluation also reveals the impact of various cost parameters on the profit objective.