Survivability quantification of real-sized networks including end-to-end delay distributions

In a telecommunication network it is essential to provide virtual connections between peering nodes with performance guarantees such as minimum throughput, maximum delay or loss. Critical services in telecommunication network should be continuously provided even when undesirable events like sabotage, natural disasters, or network failures happen. The design, construction and management of network infrastructure and service platforms aim at meeting such requirements. In this paper we consider the network's ability to survive major and minor failures in network infrastructure and service platforms that are caused by un-desired events that might be external or internal. Survive means that the services provided comply with the requirements even in the presence of failures. The network survivability is quantified as defined by the ANSI T1A1.2 committee [2] defined as the transient performance from the instant an undesirable event occurs until steady state is reached. In this paper we assess the survivability of a network with virtual connections (VCs) exposed to link or node failures. The performance measure of interest here is not just the mean delay but packet delay distributions for each virtual connection. The analytic approach that we use is verified against simulations of a real network topology and the results show very good correspondence between the two.