Mobile data caching in wireless networks

Abstract

Nowadays, mobile ad hoc networks have obtained tremendous popularity and lots of applications are widely used in such networks. Bluetooth, 802.11 (Wi-Fi) and so on are becoming very popular in the civilian sphere, through which more and more data can be generated and shared. Many applications such as multimedia streaming, online games, and P2P file sharing are examples in such wireless environments. An ad hoc network is a wireless network where wireless devices are connected into a multi-hop supported network. Its component nodes can be portable computer devices such as sensors or wireless devices. While such networks were mainly used in the military field, its scope of application is becoming increasingly broad as technology develops. In recent years, research on ad hoc networks in civil and commercial fields is duly noted. In the civilian sphere, ad hoc networks can be used for disaster relief (e.g., in the events of flood or earthquake, cable communication facilities are likely to suffer damage and can not communicate normally, calling for ad hoc networks to be set up as an emergency communications channel to ensure smooth rescue work to be conducted). From the application perspective, an ad hoc network can be termed as a Mobile Peer to Peer (or MP2P for short) network. Among the interesting features, a MP2P network has independence, dynamism in network topology, limited wireless communication bandwidth, and distributed network characteristics. For example, the life cycle is typically short, with limited physical security features; also, it has a relatively low efficiency on data transmission. To solve these problems, an effective way is to set up node caching in order to effectively reduce the network data transmission. In addition, the wireless users’ own personal choices contribute to the many other factors, including multiple types of mobile devices and wireless network environments. In other words, mobile devices, mobile network technology providers both have heterogeneous characteristics. In this thesis, we focus on the problem of mobile caching in Mobile Peer to Peer (MP2P) networks. The issues to be studied include parameters’ optimization on the base stations, mobile cache update, mobile cache indexing, cache data search, and mobile cache placement.