The Research On Key Technologies Of Resource Sharing In Campus Network Based On P2P

With the development of software and hardware, the popularization of computers and the constant expansion of campus network, campus network is becoming an important platform, with which the teachers and students will share resources. The technology of resource sharing in campus network has gradually become a research focus at the same time. The so-called resource sharing of campus network is that a part of users in campus network provide their own resources in a free way available for other computer users who need them, in order to satisfying people's demand for resources.The traditional technology of resource sharing in campus network is based on C/S (Client/Server) model as well as B/S (Browser/Server) model. In both models, all the shared resources are centrally located in the central server, when an user node need to access a shared resource, it can directly access the central server and then download the resources from it, so this model has a lot of merits such as: a simple structure, easy management, quick access and so on. However, at the present time the user nodes are in the trend of explosive growth and more and more large-capacity files are transferred in the network, these mutations bring a series of issues to the traditional network model, for instance: the powerful central servers are becoming overwhelmed, the scalability of network is greatly limited, the central servers become the bottleneck to access, the storage capacity of hard drives is not enough to storing a lot of resources, the resources'management and updating are not timely and so on. In addition, the heterogeneity of the Internet is also an important reason contributed to the resources of network can not be fully shared. Therefore it is very necessary to research and explore the scheme of resource sharing for campus network.An effective means to solve the above problems is improving the scheme of resource sharing for campus network continuously, namely, distributing information resources more availably as well as reasonably, and enabling every node in the region to use information resources farthest within a certain range, so that resources in the network can be used fully. And the new scheme of resource sharing for campus network takes region, quantity and time as harmonious factors. In order to share resources in campus network and overcome the deficiencies of traditional campus network in resource sharing, this paper introduces P2P technology into researching and exploring the scheme of resource sharing for campus network. P2P technology is a network technology with the purpose of resource sharing, and at the present time it has become a popular research. P2P, namely is the abbreviation of peer-to-peer in English, equals peer-peer connections or peer-peer networks in Chinese, and it is often referred to P2P. P2P can share resources and services of computers by exchanging directly.The main work of this paper is as follows:First, the idea of dividing the campus network into a number of peer to peer regions is given. This idea is proposed in accordance with an important characteristic that some users'behaviors are similar in campus network. For example, the entire campus network can be divided into "peer to peer regions of teaching buildings", " peer to peer regions of dormitory buildings ", " peer to peer regions of laboratories " and so on The principle of zoning is that the different peer nodes belong to different IP subsection.Second, an improved hybrid P2P network model is structured. This model uses super-node groups to take the place of single super nodes. Then this paper describes the implementation's process of the peer nodes'discovery in the network, the super nodes'selection and the peer regions'management in detail.Third, a suit of integrated cooperative caching strategy is proposed based on the characteristic of divisional hybrid P2P network model. This integrated strategy concretely includes access control strategy, cache replacement strategy and cache consistency strategy. Access control strategy uses "threshold value" and relationship of location between two nodes to select the data to be cached. Cache replacement strategy chooses the data which will be replaced by the "Cost" function that is decided by three factors: data popularity, data size and distance between two regions. Data consistency strategy combines benefits of Plain-Push and Pull-Every-time and then makes improvements.Finally, simulation experiment is given. Based on the Trace-Driven simulation technique, the above divisional hybrid P2P network is simulated. Then the output results of this simulation experiment are analyzed to test the validity and feasibility of these strategies.