| Nowadays, mobile Ad Hoc network has obtained quickly development and lots of application will be widely used in such kind of network. Bluetooth,802.11 (Wi-Fi) and so on will be very popular in the civilian sphere, which makes wireless networking gradually grown into a very important part to obtain data. Ad hoc network is popular this day, it is obvious that many applications such as cooperative web browser, and P2P file sharing and P2P multimedia streaming service will be widely developed in such kind of network environment.The foundation of our research is ad hoc network, which can also be denoted as Mobile Peer to Peer network (MP2P) in applicaton layer. Ad hoc network is a wireless network where wireless devices are connected into a multi-hop wireless network. Its composition can be a portable computer device such as sensors or even as wireless devices. While such networks are mainly used in military field, but as technology develops, its scope of application will become increasingly broad. In recent years, ad hoc network research in civil and commercial fields have also been duly noted. In the civilian sphere, ad hoc network can be used for disaster relief. In the event of flood, earthquake, cable communications facilities are likely to suffer damage and can not normally communicate, through the ad hoc network can quickly set up an emergency communications network to ensure the smooth progress of rescue work to complete the emergency communications. Ad hoc network can be used for communications in remote or underdeveloped areas. In these areas, because of cost, geographical environment, often because there is no wired communication infrastructure, ad hoc network can solve the communication problems in these environments. It can also be used for temporary communications needs, such as business meetings that need to communicate with each other. While communication between the participants in the existing wired communication systems can not meet the communications needs of the circumstances, it can be done through the ad hoc network communication tasks.This network has the independence, dynamic changes in network topology, limited wireless communication bandwidth, the network distributed characteristics, life cycle is short, limited physical security features, that is, its relatively low efficiency of data transport, how to solve this problem? The most effective way is to set up the network node cache in order to effectively reduce the network data transmission.In addition, the wireless user's own personal choice and many other factors, multiple types of mobile devices and wireless network environments will need to be fast networking devices. To this end, mobile devices, mobile network technology providers have heterogeneous characteristics, in order to address these issues; we focus on most fields of cache in Mobile Peer to Peer (MP2P) networks. The structure of this paper is organized as follows:1) Firstly, we discuss an evolution based algorithm for parameters optimization of cache updating in wireless network with both mobile client and base station. Our scheme is used to solve the low efficiency of dynamic user requests process problem in mobile base stations. Evolution based optimization method is used to make the base station to adapt to dynamic user requests. Our experiments are conducted by compaing the proposed EBHA (Evolution Based Hybrid Algorihtm) with LFU, LRU and FSR.2) Secondly, a heuristic cache path generation algorithm is proposed for cache data finding in a MP2P network. Optimization algorithms have been proposed for cache path generation for quickly cached data access in the whole network for effective data accessing. Our experiments are compared with the cache path generating strategy which takes no consideration on the heterogeneous properties of every node. By the experiments, the efficiency of the proposed schemem is proved.3) Thirdly, a heterogeneous wireless network and its caching schemes are discussed. The proposed shcme solve the problem of effectively divide the cache data into different kinds of nodes. As mobile nodes in such kind of network have different inner properties such as cache size, data transmission delay and so on. The mobile nodes are divied into three kinds which can be defined as "Super Nodes", "Middle Nodes" and "Weak Nodes". Different kinds of cache scheme have been adaptively designed for different kinds of mobile terminals in the network. A number of experiments are conducted to be compared with different kinds of cache updating schemes as:LFU, LRU and FSR. Then the efficiency of the proposed scheme is proved.4) In the fourth part, our thesis propose the cache data finding algorithm in heterogeneous network, such kind of algorithm is based on A* heuristic algorithm in mobile peer to peer network. The proposed scheme solve the problem on how to quickly find the needed data in heterogeneous mobile peer to peer network which contains the nodes with different kinds of inner properties. The proposed scheme is named as SPF-A* (Super Peer First A*), in our experiment, the compared algorithms are that only consider the different properties of the mobile node (SPF), or only consider the optimizated path generation (A*) and random finding (RAND). By the experiments, the efficiency of the proprosed schemes is proved.5) At last, a heuristic data finding algorithm is designed to adapt to such kind of network. Cache/Replication placement algorithm has been widely studied as a classical NP-hard problem. For example, in graph theory lots of work has been conducted, however, few works have been designed for the cache/replication placement algorithm combining with the cache data updating for optimization of mobile data access. The corresponding scheme is developed as a combination of cache placement and updating. Our research proposes combined herisitic cache data placement and updating in mobile peer to peer environment. The research is devoted to the problem of using traditional data placemnt in mobile peer to peer network environment and combing placement and updating in such kind of network. The experiment compare the algorithms of global placement, local placement, cluster based placement and random placement. A cache service strategy based on distributed cache placement and distributed cache updating is proposed in the MP2P network, and experiment studies have validated the efficiency of the strategy.
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