<![CDATA[P2P file sharing system in campus networks has attracted most of campus users, which can share many useful study and software files and entertainment resource. How to solve “Free Riders" and "Tragedy of Common" widespread problems has become the crucial for P2P system in campus network. In this paper, an incentive mechanism algorithm IMA based on contribution value has been proposed. According to the characteristics of file sharing system in campus network, the rules of the IMA are quantitative for sharing factors such as sharing files size and sharing rate, sharing time and files types. Experimental results and analysis show that the IMA for P2P system can effectively motivate user to share its resource and decease the selfish users, which can take the fairness and efficiency into account in P2P file system. DOI: http://dx.doi.org/10.11591/telkomnika.v10i6.1397]]>
