01841nas a2200205   4500008004100000245008900041210006900130260000900199300001400208490000600222520116600228653002101394653001701415653001601432100001801448700001701466700001801483700001701501856011701518       2010                        eng d00aFile replication method based on demand forecasting of file download in P2P networks0 aFile replication method based on demand forecasting of file down  c2010  a247 - 2530 v83 aIn peer-to-peer (P2P) networks that support file-sharing services, the level of access demand can vary widely between different files. Since fewer nodes store files for which there is a lower demand, these files are more likely to be lost from the P2P networks if users leave the network or delete the files. File loss can cause users to seek alternatives to P2P services, and lead to degradation in service quality. We propose and evaluate a replication method based on demand forecasting that aims to prevent the loss of low-demand files. In this method, the number of file replicas to be placed is determined based on the forecast demand for the file, so that the loss of low-demand files is likely prevented by placing replicas at nodes that frequently use P2P services. Based on simulation results, we compared our proposed method with basic replication methods in terms of the number of files and the amount of storage used. Our experimental results show that the proposed method prevents file loss by preserving lowdemand files over extended periods of time. We also confirmed that the node storage resources consumed by this method are efficiently used.10aP2P file sharing10aP2P networks10aReplication1 aKobayashi, M.1 aKageyama, J.1 aShibusawa, S.1 aYonekura, T.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-79960687658&partnerID=40&md5=3db4c30b2db7743416ab3f4cb69524b301975nas a2200205   4500008004100000245009500041210006900136260000900205300001400214490000600228520128200234653002801516653001001544653002701554653001701581100001701598700001501615700002201630856011701652       2006                        eng d00aPeer-to-peer content search supported by a distributed index in a publication/search model0 aPeertopeer content search supported by a distributed index in a   c2006  a175 - 1830 v43 aPeer to-peer networks (P2P) are considered a valid approach for the construction of distributed systems. Further research projects in the last few years have focused on using this kind of networks as an alternative for solving different situations that have traditionally required centralized servers, such as search engines. This paper deals with the problem of content search in highly distributed and dynamic environments. We propose and evaluate a distributed index model built upon a peer-to-peer network which supports complete indexing of text documents and allows searching by content. A distinctive feature of this proposal is that it requires no specific network topology or hierarchy. Evaluations with different settings were performed by simulating a 10,000-node network, where each node had the capability to share documents. With regard to the traffic generated, experiments show an improvement in efficiency of between 84% and 93% over similar systems like Gnutella. The evaluation of retrieval performance using a test collection showed that the P2P system was able to achieve the same level of performance as the centralized system. It was also found that the amount of traffic generated by this model varies between 80 and 225 Kb per set of query and answers.10aDistributed index model10aNodes10aP2P network evaluation10aP2P networks1 aTolosa, G.H.1 aPeri, J.A.1 aBordignon, F.R.A.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-33749394455&partnerID=40&md5=1ab83251bfe0f9c3bd58f562a6312336