Patent US 7,782,880

A peer to peer network, a method, a computer program product for a new node joining the network and a computer readable medium are disclosed. The peer to peer network comprises a plurality of nodes and a new node. Each of the nodes has its own partner list. Each of the partner lists records nodes that are able to provide data to the owner of the partner list. The nodes recorded in the partner list are called the partners of the owner of the partner list. When the new node intends to join the network, each of the nodes of the network decides whether to accept the new node according to the number of its partners but not according to a random manner. The stability of the network can be enhanced and the load of the network can be balanced.