Optimal Design of Linear Network Coding for Information Theoretically Secure Unicast
In this paper, the authors study the optimal design of Linear Network Coding (LNC) for secure unicast against passive attacks, under the requirement of Information Theoretical Security (ITS). The objectives of their optimal LNC design include satisfying the ITS requirement, maximizing the transmission rate of a unicast stream, and minimizing the number of additional random symbols. They first formulate the problem that maximizes the secure transmission rate under the requirement of ITS, which is then transformed to a constrained maximum network flow problem. They devise an efficient algorithm that can find the optimal transmission topology.