In the peer-to-peer network, every node shares the same position and every node is both client and server, i.e, every node receives the services and provide the services as well.

For the fast development of the P2P technology, the storage pattern will change from the current “centralized content” pattern to “marginal content” pattern which will greatly change the state that large web sites dominates, and return “non-centralized” condition to return the rights to the clients.

P2P technology has wide and board application domain, now mainly focus on the application of file exchanging, distributed computing, distributed searching and E-business. We begin with online TV