Unsplittable Flows
نویسنده
چکیده
An unsplittable flow in a multicommodity network is a flow that routes each commoidty on a single path. In this paper, we introduce the unsplittable flow problem and an open conjecture of Goemans, which states that given a fractional flow it is possible to construct an unsplittable flow that only overflows each edge by at most the maximum demand of a commodity. We provide an intuitive explanation of the proofs of the conjecture for the following two special cases: unweighted graphs [1], and weighted 2-tier graphs for which the unsplittable flow problem is equivalent to a particular scheduling problem [2]. Then, we describe our unsuccessful attempt at extending the proof of the conjecture for 2-tier graphs to more general 3-tier graphs and discuss the difficulties and limitations of our approach.
منابع مشابه
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