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IADIS International Conference WWW/Internet 2010after a period of time, collaborators will achieve better reputation with owner nodes and free riders will staywith reputation zero.When rogue peers start to reply content requests and send bogus pieces, all involved requesting nodesmust blacklist the rogue nodes. Hence, the expected result is that after a short time, rogue peers are unable tosend bogus pieces and their reputation must stay zero for all the system, since they do not collaborate.The simulation rounds run for 5000 s. A requesting node asks for contents one by one and when itfinishes a download, a new download is engaged immediately, such that the system is in constant activity.Figure 1 shows the results of the simulations, with the download success rate of honest peers, rogue peers andfree riders collected every 500 s of simulation. We assume that, in our simulations, nodes do not change theirstrategies, such that an honest peer remains honest for the entire simulation.Figure 1. Successful download rate of honest peers, rogue peers, and free ridersNote that, even with honest peers, there is no full download success rate, since some pieces fail to bedownloaded, due to the link failures caused by node mobility and collisions.Figure 1 shows a substantial reduction on the success of rogue peers download rate. Also free riding isminimized, after a period. In the simulations, we have used a small content to be downloaded. Recall thatwhen a content download finishes, a new download starts. Hence, for new contents, potentially new ownersare requested and so free riders keep receiving some pieces, which explain the smoothly declined chart, untilfinally be detected by a sufficient quantity of nodes to be fully restrained.5. CONCLUSIONIn this paper we have addressed the problem of discouraging rogue peers in P2MAN, which is a multicastP2P content distribution for MANETs. We have adopted a modified version of the Network of Favors toP2MAN, as a lightweight decentralized reputation scheme. In the modified version we have incorporated ablacklist feature to help NoF fighting against rogue peers in P2MAN. Also, we have defined the concept ofP2MAN node health, in efforts to model resource constraints of mobile wireless nodes in the context ofcontent distribution on MANETs. Through simulations using NS-2, we have shown that our approach issufficient to minimize rogue peer activities, reducing the success rate of rogue peers to almost zero.225