Congestion control with adaptive multipath routing based on optimization

The paper considers a TCP/IP-style network with flow control at end-systems based on congestion feedback, and routing decisions at network nodes on a per-destination basis. The only generalization with respect to standard IP is that routers split their traffic, for each destination, among their outgoing links. We pose two optimization problems, that generalize and combine those used in the congestion control and traffic engineering literature. In contrast to other work in multipath congestion control, we use variables that are available at each node (source or router). We prove that decentralized algorithms built by combining primal or dual congestion control with adaptation of router splits, converge globally to optimal points. Some comments on practical implications of these results are given.