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arXiv · 1701.03877

Cooperative Multi-Sender Index Coding

Min Li·Lawrence Ong·Sarah J. Johnson
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Abstract

In this paper, we propose a new coding scheme and establish new bounds on the capacity region for the multi-sender unicast index-coding problem. We revisit existing partitioned Distributed Composite Coding (DCC) proposed by Sadeghi et al. and identify its limitations in the implementation of multi-sender composite coding and in the strategy of sender partitioning. We then propose two new coding components to overcome these limitations and develop a multi-sender Cooperative Composite Coding (CCC). We show that CCC can strictly improve upon partitioned DCC, and is the key to achieve optimality for a number of index-coding instances. The usefulness of CCC and its special cases is illuminated via non-trivial examples, and the capacity region is established for each example. Comparisons between CCC and other non-cooperative schemes in recent works are also provided to further demonstrate the advantage of CCC.

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Min Li, Lawrence Ong, Sarah J. Johnson. 2018-09-05. Cooperative Multi-Sender Index Coding. https://doi.org/10.1109/tit.2018.2869161

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