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
A Layered Caching Architecture for the Interference Channel
TL;DR: This paper studies the two-user Gaussian interference channel in which caches are placed at both the transmitters and the receivers, and proposes a separation strategy that divides the physical and network layers.
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On Locally Decodable Index Codes
TL;DR: In this article, a client-aware approach to index coding is proposed, where the objective is to minimize the rate for a given value of locality and vice versa, and the coding scheme based on fractional coloring of the interference graph is optimal for this locality.
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Centralized Caching with Unequal Cache Sizes
TL;DR: Numerical evaluations show that the proposed caching scheme improves upon the best existing explicit scheme by having a lower worst-case load, and performs within a multiplicative factor of 1.11 from the optimal scheme with uncoded placement and linear coded delivery.
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A New Design of Private Information Retrieval for Storage Constrained Databases
TL;DR: A new SC-PIR design idea is proposed using novel storage placement schemes that significantly reduce the message size requirement while still meeting the capacity of SC- PIR.
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Coded Caching Over Multicast Routing Networks
TL;DR: This work extends the MAN scheme to a class of two-hop wired-wireless networks including one server connected via fronthaul links to a layer of helper nodes (access points/base stations), which in turn communicate via a wireless access network to users, each equipped with its own cache.
References
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