Improving Fairness and Stability in Network by Optimizing NUM(Network Utility Maximization) Problem

This paper studies network resource allocation between users that manage multiple connections, possibly through different routes, where each connection is subject to congestion control. Our goal of network efficiency and fairness is the rate allocation between users, in a manner that optimizes a user-centric NUM(Network Utility Maximization) problem. In a first proposal, cooperative users control their number of active connections based on congestion prices from the transport layer to emulate suitable primal-dual dynamics in the aggregate rate. For the case of non-cooperative users, network stability and user-centric fairness can be enforced by a utility-based admission control. We also study stability and fairness issues when routing of incoming connections is enabled at the edge router. The proposed algorithms are implemented at the packet level in ns2 and demonstrated through simulation.