Dynamic Network Control for Confidential Multi-hop Communications

We consider the problem of resource allocation and control of multihop networks in which multiple source-destination pairs communicate confidential messages, secretly from the intermediate nodes. We pose the problem as that of network utility maximization, into which confidentiality is incorporated as an additional quality of service constraint. We develop a simple, and yet optimal dynamic control algorithm which combines flow control, routing and end-to-end secrecy-encoding. In order to achieve confidentiality, our scheme exploits multipath diversity and temporal diversity due to channel variability. Our end-to-end dynamic encoding scheme encodes confidential messages over many packets, to be combined at the ultimate destination for recovery. We also evaluated our scheme numerically under various conditions to show its efficacy.