Design algorithms for path-level grooming of traffic in WDM metro optical networks

Recent research in new architecture design for wavelength-routed networks is focused on grooming (aggregation) of traffic at the optical layer. Typically, this is achieved in three steps: (1) configure the circuit in the form of a path or a tree; (2) use optical devices such as couplers or splitters to allow multiple users to share a circuit through point to point (P2P), point to multipoint (P2MP), multipoint to point (MP2P), or multipoint to multipoint (MP2MP); and (3) provide an arbitration mechanism to avoid contention among end users. We compare the performance of architectures that aggregate traffic at the path level. Based on extensive simulations, we conclude that, for the studied topology and traffic, (1) MP2MP outperforms other architectures by multiple orders of magnitude in single-hop scenarios, (2) P2P performs the best in multihop transceiver-constrained scenarios, and (3) P2MP performs the best in multihop wavelength-constrained scenarios.