A Survey of Advanced Search Techniques in Unstructured P2P Networks

In unstructured peer to peer networks, any peer might share any file with other nodes. This uncertainty of where a specific file is located, makes the search problem in unstructured networks complicated. So far, many search algorithms have been proposed which try to maximize the success rate of an initiated query and minimize the imposed cost of search. In this paper, we survey newly introduced approaches to overcome search process problems. By reviewing these strategies and comparing them with previous search methods, we propose a new classification of informed search algorithms and we conclude that regarding this classification, informed search algorithms should be applied in less dynamic networks while blind search algorithms can be used in small networks. We believe that this taxonomy and the new classification can be useful as a guide for future search algorithm design.