Explicit Inner and Outer Bounds for Multi-source Multi-sink Network Coding

In multi-source multi-sink network coding, messages across different sources are coded to increase the overall throughput. The various types of coded information in the network significantly complicate the determination of its capacity region. In this work, we derive explicit inner and outer bounds for acyclic multi-source multi-sink networks based on a cut-based network decomposition technique and a role-based information characterization technique. In particular, we derive a linear programming inner bound for regular K-pairs acyclic three-layer networks and a network sharing outer bound for arbitrary acyclic multi-source multi-sink networks. The techniques used in this paper reveal some of the basic mechanisms of multi-source multi-sink network coding