Performance of WDM mesh networks with limited traffic grooming resources

While a single fiber strand in wavelength division multiplexing (WDM) has over a terabits-per-second data rate and a wavelength channel has over a gigabits-per-second transmission speed, the network may still be required to support traffic requests at rates that are lower than the full wavelength capacity. To avoid assigning an entire lightpath to a small request, many researchers have looked at adding traffic grooming to the Routing and Wavelength Assignment (RWA) problem. In this work, we consider the RWA problem with traffic Grooming (GRWA) for mesh networks under dynamic lightpath connection requests. Like RWA, GRWA is also NP-Complete. While most of the previous work in this field focuses on optical networks without grooming or with full grooming capabilities, in this work we study the blocking performance of optical networks with sparse traffic grooming resources. This paper proposes a novel heuristic for dynamic traffic grooming in WDM mesh networks, where connections arrive one at a time and hold for random time durations. The strength of the proposed heuristic stems from its simplicity, applicability to large-scale networks, and efficiency compared to other heuristics proposed in the literature. Our simulation results demonstrate that deploying traffic grooming resources on the edge of optical networks is more cost effective and results in a similar blocking performance to that obtained when distributing the grooming resources throughout the optical network domain.