The invention discloses an on-line video-on-demand
system based on P2P, comprising a
server terminal and
client terminals. The
server terminal comprises a secret key providing
server, a Tracker server of the BT protocol, and an NAT boring server. Each
client terminal is composed of a Proxy process and a player process. Each Proxy process establishes connection with the Tracker server of the BT protocol and an Internet through a
BitTorrent P2P protocol so as to obtain encrypted video data. Each player process communicates with the Proxy process through a
hyper text transport protocol (HTTP) and communicates with the secret key providing server through hyper text transport protocols (HTTPS) to obtain a secret key. The Proxy processes also communicate with the NAT boring server which is in charge of
NAT traversal communication with the two
client terminals. The on-line video-on-demand
system based on P2P performs one-time static
encryption of video files at a background, and distributes the video files to users through P2P; and secret keys required for videos
on demand are obtained from the secret key providing server.