 
Summary: A Randomized Online Algorithm for Bandwidth
Utilization
Sanjeev Arora
Princeton University
Bo Brinkman y
Princeton University
Abstract
Protocols for data transmission over an IP computer network should
not only lead to eÆcient network utilization but also be fair to dierent
users. Current networks accomplish these goals by some form of endto
end congestion control. Existing protocols, however, assume somewhat
altruistic behavior from hosts. Karp et al. [6] have initiated a study of
whether or not a single host's optimum strategy (in a system where other
hosts are well behaved) is altruistic. We carry this exploration further by
developing an eÆcient randomized algorithm for bandwidth utilization in
their model. The competitive ratio of this algorithm is optimal up to a
constant factor. Karp et al. had earlier studied the deterministic case and
left open the randomized case.
What may be of some interest is that our algorithm is essentially the
classical MIMD (multiplicative increase, multiplicative decrease) strategy,
