Journal of Computer Applications ›› 2018, Vol. 38 ›› Issue (5): 1453-1457.DOI: 10.11772/j.issn.1001-9081.2017112710

Previous Articles     Next Articles

Cache placement optimization scheme in D2D networks with heterogeneous cache capacity

LONG Yanshan, WU Dan, CAI Yueming, WANG Meng, GUO Jibin   

  1. College of Communications Engineering, Army Engineering University of PLA, Nanjing Jiangsu 210007, China
  • Received:2017-11-16 Revised:2017-12-27 Online:2018-05-10 Published:2018-05-24
  • Contact: 吴丹
  • Supported by:
    This work is partially supported by the National Natural Science Foundation of China (61671474), the Jiangsu Provincial Science Fund for Excellent Young Scholars (BK20170089).

多缓存容量场景下的D2D内容缓存布设优化方案

龙彦汕, 吴丹, 蔡跃明, 王萌, 郭继斌   

  1. 中国人民解放军陆军工程大学 通信工程学院, 南京 210007
  • 通讯作者: 吴丹
  • 作者简介:龙彦汕(1989-),女,山东荣成人,博士研究生,主要研究方向:D2D缓存网络、随机几何、资源管理;吴丹(1983-),女,四川成都人,副教授,博士,主要研究方向:D2D通信、博弈论、资源管理;蔡跃明(1961-),男,福建永泰人,教授,博士,主要研究方向:协同无线网络、无线物理层安全、信号处理;王萌(1983-),男,山东临沂人,讲师,硕士,主要研究方向:D2D通信;郭继斌(1973-),男,河北唐山人,讲师,硕士,主要研究方向:协同通信、资源分配。
  • 基金资助:
    国家自然科学基金资助项目(61671474);江苏省优秀青年基金资助项目(BK20170089)。

Abstract: Limited and heterogeneous cache capacity is one of the key parameters which affect the cache efficiency in Device-to-Device (D2D) caching networks. However, most of existing literatures assume all users have homogeneous cache capability. In this regard, cache placement optimization is necessary for practical scenarios with heterogeneous cache capacities. Considering the mobility and random distribution of terminal users, users with different cache capacities were modeled as mutually independent homogeneous Poisson point processes with stochastic geometry. Moreover, the average cache hit ratio was derived with considering both self-offloading and D2D-offloading cases. Finally, a Joint Cache Placement (JCP) algorithm based on coordinate gradient optimization was proposed to obtain the optimal cache placement scheme which can maximize the cache hit ratio. Simulation results show that the proposed JCP can achieve larger cache hit ratio than the existing cache placement schemes.

Key words: Device-to-Device (D2D) caching network, heterogeneous cache capacity, stochastic geometry, cache hit ratio, cache placement optimization

摘要: 在终端直传(D2D)缓存网络中,用户有限且各异的缓存能力是制约缓存效率的一个关键参数,然而现有文献大多考虑不同用户具有相同的缓存能力,针对这一不足有必要进行用户具有不同缓存容量下的D2D内容缓存布设方案优化。首先,鉴于用户终端的移动性和随机分布特性,利用随机几何理论将网络中不同缓存容量的用户节点建模为相互独立的齐次泊松点过程;其次,考虑本地卸载和邻近D2D链路卸载两种内容卸载方式,推导得到网络缓存命中率;最后,将最大化缓存命中率作为优化目标函数,提出了基于坐标梯度的联合缓存布设(JCP)算法,从而得到多用户多缓存容量场景下的内容缓存布设方案。仿真结果表明,与现有的缓存布设方案相比,由JCP得到的缓存布设方案可以有效提高缓存命中率。

关键词: 终端直传缓存网络, 多缓存容量, 随机几何, 缓存命中率, 缓存布设优化

CLC Number: