Efficient Placement of Splitters in Optical WDM Network

In this paper, we investigate the splitter placement problem in an optical WDM network. The goal is to select a given number of MC nodes in the network such that the overall link cost of a multicast session is minimized. We present an exact formulation in integer linear programming ( ILP ) to find a set of trees that connects a source to a set of destination nodes. Then, four algorithms based on network topology metrics are proposed to select a given number of MC nodes in the network such that the overall link cost of a multicast session is minimized. The efficiency of the proposed algorithms is verified by simulation results.

IMPACT OF TOPOLOGY ON THE MAXIMUM MULTICAST THROUGHPUT IN COMMUNICATION NETWORKS WITH NETWORK CODING

Network coding has been shown to be an effective coding technique to improve the throughput of a multicast session in a communication network. In general, an undirected network can be used to model a communication network in which nodes at both ends of a link can exchange messages. For a single multicast session in an undirected network with network coding, the maximum throughput can be estimated based on the minimum maxflow between the source node and the destination nodes. In this letter, we evaluate the impact of the network topology on the maximum multicast throughput of a network-coded communication network. In particular, the scalefree network, which represents the topology of most man-made networks including the Internet, will be compared with the random network. The maximum throughputs of the multicast sessions are evaluated for different choices of source and destination nodes. It is found that network coding can achieve better throughput of a scalefree network only if the source and destination nodes are chosen from high-degree nodes.