Network Coding in Bi-Directed and Peer-to-Peer Networks
Network coding has been shown to help achieve optimal throughput in directed networks with known link capacities. However, as real-world networks in the Internet are bi-directed in nature, it is important to investigate theoretical and practical advantages of network coding in more realistic bi-directed and Peer-To-Peer (P2P) network settings. In this paper, the authors begin with a discussion of the fundamental limitations of network coding in improving routing throughput and cost in the classic undirected network model. A finite bound of 2 is proved for a single communication session. They then extend the discussions to bi-directed Internet-like networks and to the case of multiple communication sessions.