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Electrical and Computer Engineering

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Conference Proceeding


2010 IEEE International Symposium on Information Theory

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2010 IEEE International Symposium on Information Theory Proceedings (ISIT)



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2010 IEEE International Symposium on Information Theory

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June 13-18, 2010


Austin, TX


We consider the problem of multicasting sums over directed acyclic networks with unit capacity edges. A set of source nodes si observe independent unit-entropy source processes Xi and want to communicate Σ Xi to a set of terminals tj. Previous work on this problem has established necessary and sufficient conditions on the si -tj connectivity in the case when there are two sources or two terminals (Ramamoorthy '08), and in the case of three sources and three terminals (Langberg-Ramamoorthy '09). In particular the latter result establishes that each terminal can recover the sum if there are two edge disjoint paths between each si-tj pair. In this work, we provide a new and significantly simpler proof of this result, and introduce techniques that may be of independent interest in other network coding problems.


This is a manuscripts of a proceeding from the IEEE International Symposium on Information Theory (2010): 1853, doi:10.1109/ISIT.2010.5513422. Posted with permission.


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