Abstract:

Chord is a structured P2P network model, it has the advantages of high speed, needing no center control, extensibility, load balance, fault tolerance, etc. But, as Chord is a oneway search algorithm, when the destination node is far from the current node, the routing delay increases because of multihops. And, low ability nodes with responsibility for large numbers of search and download tasks, and the nodes join in or leave the system momentarily and frequently, which can decrease the network efficiency obviously. An improved algorithm called the bidirectional masterslave chord algorithm supports twoway search, and all the network nodes are divided into super nodes and common nodes, and the super nodes with higher evaluation results construct the main ring of Chord. The experimental results show that the improved algorithm can reduce routing hops and network delay effectively.

Key words: peer to peer;distribute hash table;chord;resource search