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
More filters
Journal ArticleDOI
Signal Processing for High Throughput Satellite Systems: Challenges in New Interference-Limited Scenarios
Ana I. Perez-Neira,Miguel Angel Vazquez,Sina Maleki,M. R. Bhavani Shankar,Symeon Chatzinotas +4 more
TL;DR: In this article, the state-of-the-art and open research challenges of signal processing techniques for very high throughput satellites (V/HTS) systems are presented for the first time, with focus on novel approaches for efficient interference mitigation.
Proceedings ArticleDOI
On caching with more users than files
TL;DR: The proposed delivery method is proved to be optimal under the constraint of uncoded cache placement for centralized systems with two files and it is shown to outperform known caching strategies for both centralized and decentralized systems.
Journal ArticleDOI
Modeling, Analysis, and Optimization of Coded Caching in Small-Cell Networks
Xuejian Xu,Meixia Tao +1 more
TL;DR: This paper investigates coded caching in a large-scale small-cell network (SCN) where the locations of small base stations (SBSs) are modeled by stochastic geometry and formulate the coded cache placement problem for AFOT maximization as a multiple-choice knapsack problem (MCKP).
Posted Content
Cache-Enabled Heterogeneous Cellular Networks: Optimal Tier-Level Content Placement
TL;DR: In this article, the authors adopt the popular random HCN model where $K$ tiers of BSs are modelled as independent Poisson point processes distributed in the plane with different densities.
Journal ArticleDOI
ADMM-Based Fast Algorithm for Multi-Group Multicast Beamforming in Large-Scale Wireless Systems
Erkai Chen,Meixia Tao +1 more
TL;DR: A low-complexity high-performance algorithm for multi-group multicast beamforming design in large-scale wireless systems by leveraging the alternating direction method of multipliers (ADMM) together with CCP is proposed.
References
More filters
Journal ArticleDOI
Network information flow
TL;DR: This work reveals that it is in general not optimal to regard the information to be multicast as a "fluid" which can simply be routed or replicated, and by employing coding at the nodes, which the work refers to as network coding, bandwidth can in general be saved.
Journal ArticleDOI
Amortized efficiency of list update and paging rules
TL;DR: This article shows that move-to-front is within a constant factor of optimum among a wide class of list maintenance rules, and analyzes the amortized complexity of LRU, showing that its efficiency differs from that of the off-line paging rule by a factor that depends on the size of fast memory.
Proceedings ArticleDOI
Distributed Caching Algorithms for Content Distribution Networks
TL;DR: This paper develops light-weight cooperative cache management algorithms aimed at maximizing the traffic volume served from cache and minimizing the bandwidth cost, and establishes that the performance of the proposed algorithms is guaranteed to be within a constant factor from the globally optimal performance.
Journal ArticleDOI
Index Coding With Side Information
TL;DR: A measure on graphs, the minrank, is identified, which exactly characterizes the minimum length of linear and certain types of nonlinear INDEX codes and for natural classes of side information graphs, including directed acyclic graphs, perfect graphs, odd holes, and odd anti-holes, minrank is the optimal length of arbitrary INDex codes.
Journal ArticleDOI
Comparative Models of the File Assignment Problem
TL;DR: This perspective exposes the further research which is necessary in order to provide a truly satisfactory solution to the file assignment problem.