Research On Cooperation Caching Mechanism In Mobile Social Network Environment

A mobile social network as a new type tolerant network(DTN) obtained the rapid development in recent years. Due to the mobility of nodes in the MSN, nodes are difficult to maintain the stability of the end-to-end communication link. This makes traditional data distribution strategy cannot be applied directly in MSN environment; therefore how to improve the efficiency of data access in mobile network is imminent. Caching technology is widely used in various fields to support the low communication overhead and low response delay of data distribution and sharing. In this paper, we from the cache placement, contact duration limit, and cache space limit three aspects to consider, propose a contact duration aware cooperation caching approach. Finally, through a concrete example we illustrate the deployment strategy of the agreement.1) Cache placement: In mobile social network, the node has a high degree of mobility; resulting in between nodes are difficult to maintain the stability of end to end communication link. Nodes through contact each other to realize the data transmission, due to the probability of contact between different nodes they have different status in the network.In this article, through calculating the value of? ? ? ? ? ??ICCTETETE ? to measure the importance of nodes. The value not only shows the node connectivity but also hints the node has more contact time for data transmission.2) Contact duration limit: Because of the short contact duration, only a small amount of data can be transferred during each contact in mobile social network. This may result in data transmission between the nodes cannot be finished in the process of a contact, to a certain extent, affect the performance of data transmission. In this paper,through the method of cutting data fragmentation solved a contact cannot do the whole data transmission problem, and use the coding technique to solve the problem of possible coupon collection.3) Cache space restrictions: In the mobile social network, the node is a social user's intelligent terminal equipment. And the problem that the intelligent devices are in a small storage space, resulting in the network node cache space limit, therefore in the node to store all the valid data is impossible. In this paper, we use the contact history information between nodes to calculate each node's longest time, which is in contact with other nodes, and as a basis for defining the upper limit of the amount ofdata that can be cached in a node, and make full use of node's cache resources.