Network Coding: Theory and Reality

Recent research in the domain of network coding has promised a complete paradigm shift for wired and wireless networks. In case of wired networks, improvements in the network capacity especially magnify for multicast scenarios. For wireless networks, the inherent broadcast nature of the medium provides ample opportunities for intelligent mixing of the information. The two major benefits offered by this approach are: throughput improvements for the whole system and a high degree of robustness. In theory, the gains are guaranteed and vary form a few percent to several folds depending on traffic patterns, congestion levels and other network characteristics. A few recent practical system implementations have also validated the gains, but all of them trade with the complexity of this paradigm. This paper discusses the state of the art research in this domain both from a theoretical and a systems perspective. We describe the manifold applications of this approach in different kinds of networks, with the associated degree of complexity and the practical considerations. We discuss how coding-aware schemes can provide energy and throughput gains for wireless networks. Finally we present some novel and interesting open problems which could be researched further in this field.