The Study On Caching Stratrgy For Content Centric Social Wireless Networks

As the explosive growth of the number of smart devices, Social Wireless Networks (SWNs) have been applied to various environments for multi-media content dissemination with the popularity of social applications. SWNs are formed by mobile devices, sharing common interests in contents, and physically gathering together in public places.Content Centric Networking (CCN) is a candidate future Internet architecture that gives favorable promises in SWNs instead of IP-based Networks, to cope with short-lived connectivity and dynamic topology in wireless environments. The CCN architecture, relying on in-network caching can provide faster content access while reducing traffic in the network. Therefore, CCN can be introduced into SWNs to improve the efficiency of content delivery.This thesis is based on the National Natural Science Foundation"The Research of Caching for Content Centric Mobile Social Networking" and the Open Foundation of Beijing Key Laboratory of Network System Architecture and Convergence "The Research of Caching for Content Centric Wireless Networks based on User Preferences".The work focuses on in-network caching in Social Wireless Networks. To improve the efficiency of caching, the research studies the caching diversity and reusability.In this thesis, first of all, the basic concepts and key issues of CCN are introduced and the research present condition of caching technologies for CCN is summarized. Especially, the problem of caching in Social Wireless Networks is analyzed. In this paper, a content popularity and node level matched based probability caching strategy is firstly proposed.By evaluating the caching property of nodes, we classify nodes into levels and assign contents to the nodes with their matched level. The proposed strategy balances the proportion of contents with different popularity, and achieves richer content diversity to improve the efficiency of caching.Then we introduce a probability caching strategy which is based on the topology potential of social space to improve the caching reusability.According the theory of social distance, which is introduced to modify the formula of the topology potential, we deduce the topology potential of social space. We use the model which considers the social attribute to make a caching decision. By making use of the broadcast about wireless channel, we improve the caching reusability and caching efficiency.Simulation results demonstrate that the proposed strategies can both achieve less content access delay and higher cache hit ratio.