QoT- and SLA-Aware Survivable Resource Allocation in Translucent Optical Networks

Survivability is a critical issue in high-capacity wavelength division multiplexing based optical networks, since even a disruption for a very short time could result in the loss of a large amount of data. Each accepted connection request brings revenue to the network. On the other hand, a service level agreement (SLA) requirement (e.g., 99.9% uptime in terms of availability) is associated with a connection, and a penalty is paid if the requirement is violated. In addition, physical impairments degrade the quality of signals as they traverse along lightpaths. In this paper, the survivable routing and wavelength assignment problem is studied for dynamic traffic in translucent optical networks considering randomly occurring failures of optical fibers and nodes, so that the quality of transmission (QoT) requirement of each connection is satisfied, and the network-level performance metric of total profit is maximized. Two heuristics are developed - the first one aims to allocate resources to each connection to minimize the expected penalty; while the other heuristic prefers to allocate the minimum possible resources to each connection. Simulation results are presented to demonstrate their effectiveness.