ISSN 1000-1239 CN 11-1777/TP

• 综述 •

### 移动机会网络中接触时间感知的协作缓存策略

1. (安徽工业大学计算机科学与技术学院 安徽马鞍山 243002) (xzheng@ahut.edu.cn)
• 出版日期: 2018-02-01
• 基金资助:
国家自然科学基金项目(61402008,61402009)；安徽省高校自然科学研究重大项目(KJ2014ZD05)；安徽省科技重大专项(16030901060)；安徽省高校优秀青年人才支持计划

### Contact Duration Aware Cooperative Data Caching in Mobile Opportunistic Networks

Zheng Xiao, Gao Han, Wang Xiujun, Qin Feng

1. (School of Computer Science and Technology, Anhui University of Technology, Maanshan, Anhui 243002)
• Online: 2018-02-01

Abstract: How to improve the efficiency of data access is always a hot topic in the research area of mobile opportunistic networks. Traditional cooperative caching techniques are commonly used to improve the performance of data access. However, the strongly independent mobility and limited contact duration of the mobile nodes render these traditional caching schemes inefficient. Firstly, a new metric, called as node important degree, is proposed to determine which node is more important to cooperative data caching. Based on this metric, a greedy algorithm is used to select initial cache nodes, and subsequently the cache data will be redistributed among these cache nodes actively as they meet each other. A novel data fragmenting strategy is suggested to adapt to the limited contact duration between nodes with the aim to make our protocol suitable for short-duration contact between cache nodes. In order to solve the coupon collector’s problem in data recovery, a randomly linear network coding method is used to encode the data fragmentations. Moreover, we describe an adaptive caching bound calculation method for each mobile node to limit the amount of data it caches, which is helpful to the rational utilization of cache space. Experimental results show that our suggested cooperative caching protocol can significantly improve the efficiency of data access in mobile opportunistic networks.