Reliable multi-path provisioning for high-capacity optical backbone mesh networks

We investigate the problem of reliable multi-path provisioning of traffic in high-capacity optical backbone mesh networks, e.g., next-generation SONET/SDH networks supporting virtual concatenation (VCAT). VCAT enables a connection to be inversely multiplexed on to multiple paths. As a result, a connection can be provisioned more flexibly, and such a multi-path provisioning approach may lead to significantly improved performance over the conventional single-path provisioning approach. This multi-path provisioning approach may also be applicable to other mesh networks such as those employing optical wavelength-division multiplexing (WDM) and multi-protocol label switching (MPLS), where the bandwidth of a connection to be provisioned exceeds the available capacity on any path based on current network state. We propose effective multi-path bandwidth as the metric to provision a connection on to multiple paths while satisfying its reliability requirements (measured in terms of availability). We show that effective multi-path bandwidth provides more flexibility and lower blocking probability without the cost and complexity associated with traditional protection schemes developed for optical WDM and MPLS networks.