Bottleneck Flow Control

The problem of optimally choosing message rates for users of a store-and-forward network is analyzed. Multiple users sharing the links of the network each attempt to adjust their message rates to achieve an ideal network operating point or an " ideal tradeoff point between high throughput and low delay. " Each user has a fixed path or virtual circuit. In this environment, a basic definition of " ideal delay-throughput tradeoff " is given and motivated. This definition concentrates on a fair allocation of network resources at network bottlenecks. This " ideal policy " is implemented via a decentralized algorithm that achieves the unique set of optimal throughputs. All sharers constrained by the same bottleneck are treated fairly by being assigned equal throughputs. A generalized definition of ideal tradeoff is then introduced to provide more flexibility in the choice of message rates. With this definition, the network may accommodate users with different types of message traffic. A transformation technique reduces the problem of optimizing this performance measure to the problem of optimizing the basic measure. V I. INTRODUCTION ARIOUS store-and-forward packet-switched computer networks have been developed in recent years. The primary function of these networks is to route messages or packets from one network location to another. Typically, the source of a message dispatches a packet to a neighboring location or node, which relays the message to another node and so forth, until the message arrives at the destination. There are a number of disciplines used by networks to funnel a large number of packets from one source to a given destination. For example, ARPANET handles each packet