Fundamental Limits of Caching
TLDR
This paper proposes a novel coded caching scheme that exploits both local and global caching gains, leading to a multiplicative improvement in the peak rate compared with previously known schemes, and argues that the performance of the proposed scheme is within a constant factor of the information-theoretic optimum for all values of the problem parameters.Abstract:
Caching is a technique to reduce peak traffic rates by prefetching popular content into memories at the end users. Conventionally, these memories are used to deliver requested content in part from a locally cached copy rather than through the network. The gain offered by this approach, which we term local caching gain, depends on the local cache size (i.e., the memory available at each individual user). In this paper, we introduce and exploit a second, global, caching gain not utilized by conventional caching schemes. This gain depends on the aggregate global cache size (i.e., the cumulative memory available at all users), even though there is no cooperation among the users. To evaluate and isolate these two gains, we introduce an information-theoretic formulation of the caching problem focusing on its basic structure. For this setting, we propose a novel coded caching scheme that exploits both local and global caching gains, leading to a multiplicative improvement in the peak rate compared with previously known schemes. In particular, the improvement can be on the order of the number of users in the network. In addition, we argue that the performance of the proposed scheme is within a constant factor of the information-theoretic optimum for all values of the problem parameters.read more
Citations
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Proceedings ArticleDOI
Local time sharing for index coding
TL;DR: A series of extensions of the index coding schemes based on time sharing by Birk and Kol, by Blasiak, Kleinberg, and Lubetzky, and by Shanmugam, Dimakis, and Langberg are presented.
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Decentralized coded caching with distinct cache capacities
TL;DR: In this article, a decentralized coded caching scheme is proposed for a content server with N files, each of size F bits, serving K active users, each equipped with a cache of distinct capacity.
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Optimized Base-Station Cache Allocation for Cloud Radio Access Network with Multicast Backhaul
Binbin Dai,Ya-Feng Liu,Wei Yu +2 more
TL;DR: This paper proposes the use of wireless multicast together with BS caching, where the BSs pre-store the contents of popular files, to augment the backhaul of C-RAN and shows considerable performance improvement of the optimized cache size allocation scheme over the uniform allocation and other heuristic schemes.
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Critical Database Size for Effective Caching
TL;DR: It is shown that the effectiveness of caching become small when the number of files becomes comparable to the square of the numberof users, and the question of to what extent caching is effective in reducing the server load is addressed.
Proceedings ArticleDOI
Erasure broadcast networks with receiver caching
TL;DR: Achievable and converse bounds for the optimal capacity-memory tradeoff are derived and new joint cache-channel coding schemes that significantly outperform naive separate cache- channel coding schemes are proved.
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