In tThis paper proposes, a distributed and scalable community discovering approach namely PDC (Power based Distributed Clustering Approach) is proposed for P2P networks. PDC adopts Power value of nodes to measure new measurement of community structure and includes newto select center node selection algorithm. Experimental results show that the effect of PDC has better effect and scalability compared to other algorithms is five percent5% higher than FDC and CDC, but the number of messages generated by PDC is nearly ten percent10% of FDC.
Following the analysis of existing distributed trust model to Ad Hoc networks, this paper presents an ID-based key management scheme using bilinear pairing. It employs the secret-sharing technique to distribute system key among a pre-selected set of nodes, called D-PKGs, which offers a collaborative private-key-generator service. The construction method not only ensures secure and efficient network-wide key update, but also establishes session key via only a single message using property of bilinear pairing. Analysis show the scheme is secure and effective.