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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Journal ArticleDOI
Error Correction in Coded Caching With Symmetric Batch Prefetching
TL;DR: An optimal linear error correcting delivery scheme is proposed for coded caching problems with symmetric batch prefetching in the absence of Prefetching errors and lower bounds are established for the optimal rate required when there are prefetched errors in asymmetric batchPrefetching.
Journal ArticleDOI
Uncoded Placement With Linear Sub-Messages for Private Information Retrieval From Storage Constrained Databases
TL;DR: An iterative algorithm is designed to solve the filling problem of storage placement where, in each iteration, messages are partitioned into sub-messages and stored at subsets of DBs.
Posted Content
Treating Content Delivery in Multi-Antenna Coded Caching as General Message Sets Transmission: A DoF Region Perspective
Youlong Cao,Meixia Tao +1 more
TL;DR: In this paper, the authors investigate the full spatial multiplexing gain in multi-antenna coded caching by transmitting all coded messages concurrently and find the minimum normalized delivery time (NDT) by searching the optimal DoF tuple in the DoF regions.
Journal ArticleDOI
On Rate Region of Caching Problems With Non-Uniform File and Cache Sizes
TL;DR: The polyhedral projection is converted into a multiple objective linear programming and an implementation of Benson’s outer approximation algorithm is used to solve the rate region of the two-file two-user caching problem.
Journal ArticleDOI
Towards Finite File Packetizations in Wireless Device-to-Device Caching Networks
TL;DR: Two combinatorial approaches of D2D coded caching network design with reduced packetizations and desired throughput gain compared to the conventional uncoded unicasting are presented and an exponential reduction of packetizations is yielded while providing a per-user throughput that is comparable to the state-of-the-art designs in the literature.
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