On Consideration of Content and Memory Sizes in 5G D2D-Assisted Caching Networks

Abstract

Device-to-Device (D2D) communication with caching technology has emerged as a promising technique for offloading the traffic and boosting the throughput of the fifth generation (5G) cellular networks. The combined impact of cache memory size of user equipments (UEs) and content sizes, which are two crucial factors in D2D-assisted caching networks, were usually ignored in the existing researches. In this paper, an optimization algorithm is proposed to maximize the cache hit probability and cache-aided throughput, with the consideration of various cache memory sizes of UEs and content sizes. Firstly, users are grouped according to the cache memory sizes and the content sizes. Then the general mathematical expressions for the optimization of cache hit probability and cache-aided throughput with the constraints of cache memory sizes and content sizes are obtained. Subsequently, a Packet Cache Strategy (PCS) algorithm is proposed to obtain the caching probability matrix with the maximum cache hit probability and cache-aided throughout by taking user caching probability of a file as a variable. Finally, numerical results show that the sizes of the requested files affect the caching willingness of users, and the proposed PCS can achieve the highest cache hit probability and the best cache-aided throughput comparing with two other existing methods. INDEX TERMS D2D-assisted caching, cache hit probability, cache-aid throughput, file size, memory size.

Constructing Effective Caches of Shortest Path Queries on Road Networks

“…To address the problem of timely cache updating in D2D caching placement, [2] explored a network coding-based socially-aware D2D caching strategy by taking geographical proximity and the social relationships of users into consideration. In D2D communication, [3] proposed an optimization algorithm to maximize the cache hit probability and cache-aided throughput by considering the combined impact of various cache memory sizes of UEs and content sizes. [4] proposed a practical and feasible replacement architecture for base station (BS) assisted wireless D2D caching networks by exploiting the broadcasting of the BS.…”

Optimal Caching Policy for D2D Assisted Cellular Networks With Different Cache Size Devices

“…Heterogeneous user activity level, different content request of users for the same content and unequal user cache size make the aforementioned challenges even more complicated. Most of the existing works, assume the cache size of devices to be equal, while according to the device model and other factors, this is an unrealistic assumption for real-world cellular networks [4].…”

“…In [9], the cache hit maximization problem in a heterogeneous wireless network has been investigated where users don't cache data and no D2D communication is available. The authors in [10]- [12] have considered a server connected to several users that have different cache sizes. The links between the server and each user and the links between devices have been assumed "error-free", coded caching is assumed, and their cost function is not a cache hit probability.…”

Clustering-based device-to-device discovery and content delivery in wireless networks

“…In the literature, studies on D2D cache placement mostly considered optimization-based approaches that disregarded practicality aspects. Optimization problems are formulated and solved in order to maximize coverage [6], of loading [7], hit ratio [9,14,15,16], minimize delay [8,11] and minimize cost [10], under constraints such as cache capacity [15], delay and coverage [16]. An optimal cache placement problem that aims to maximize of loading has been formulated and solved jointly with the D2D link establishment scheme in [17].…”