Capacity and Flow Assignment in survivable overlay networks with dual homing architecture

Due to recent developments in cloud computing and constantly increasing demand for high definition music and video content, both overlay networks and multicasting providing live streaming services along with network survivability have been gaining more and more attention in the last years. In our paper, we focus on the problem of Capacity and Flow Assignment (CFA) in survivable overlay networks. We assume that the overlay network is deployed to provide multicasting of critical data that require to be transmitted safely and with minimum possible delay. We propose to use a dual homing approach, i.e., each peer is connected to the overlay by two separate access links, to improve survivability of the overlay multicasting. We consider the following network failures: streaming server failure, overlay link failure, uploading node failure and ISP interconnection failure. The optimization problem is formulated in the form of an Integer Linear Programming (ILP) model. Moreover, we introduce a heuristic algorithm (Simulated Annealing) for the given problem and compare it with optimal results achieved by the ILP modeling (CPLEX solver). Our studies demonstrate that the Simulated Annealing (SA) method yields results close to optimum and provides better scalability comparing to ILP modeling, since SA can solve in a reasonable time much larger problem instances than ILP modeling. Furthermore, our studies show that the additional survivability requirements do not have a substantial impact on the overlay multicasting system expressed as the maximum delay in case of the CFA problem.