SRLG-aware topology aggregation for survivable multi-domain optical networks

In multi-domain optical networks, due to confidentiality and management considerations, it may be infeasible to exchange complete domain state information among domains. Topology aggregation (TA) is a widely adopted technique for aggregating a domain's detailed topology into simpler aggregated topology with limited information. In order to generate an abstracted topology that is more survivable against failures, the TA approach may also consider the presence of shared risk link groups (SRLGs), each of which defines a set of links that may fail simultaneously. We propose SRLG-aware topology aggregation approaches that can help to find a pair of inter-domain paths with a minimum set of common SRLGs. We find that constructing an aggregated topology while taking into account the SRLG distribution can help in developing a more survivable aggregated multi-domain network. Moreover, exchanging SRLG information prior to constructing the TA further increases the survivability of the aggregated topology. The performance of various TA schemes, such as single node, star, and full mesh, is also investigated.