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arXiv · 1609.02985

Placement Delivery Array Design through Strong Edge Coloring of Bipartite Graphs

Qifa Yan·Xiaohu Tang·Qingchun Chen·Minquan Cheng
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Abstract

The technique of coded caching proposed by Madddah-Ali and Niesen is a promising approach to alleviate the load of networks during busy times. Recently, placement delivery array (PDA) was presented to characterize both the placement and delivery phase in a single array for the centralized coded caching algorithm. In this paper, we interpret PDA from a new perspective, i.e., the strong edge coloring of bipartite graph. We prove that, a PDA is equivalent to a strong edge colored bipartite graph. Thus, we can construct a class of PDAs from existing structures in bipartite graphs. The class includes the scheme proposed by Maddah-Ali \textit{et al.} and a more general class of PDAs proposed by Shangguan \textit{et al.} as special cases. Moreover, it is capable of generating a lot of PDAs with flexible tradeoff between the sub-packet level and load.

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Qifa Yan, Xiaohu Tang, Qingchun Chen, Minquan Cheng. 2016-09-10. Placement Delivery Array Design through Strong Edge Coloring of Bipartite Graphs. https://doi.org/10.1109/lcomm.2017.2765629

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