Research On Key Technologies For Distributing Streaming Media Content Over P2P Network

Media streaming is becoming the mainly driving force for future broadband network applications. In a traditional client-server streaming system, the server often becomes the bottleneck due to the high bandwidth and long duration of multimedia streams, how to distribute streaming media content to a large number of hosts in a scalable way has become the key issue of multimedia research area in the last decade. IP multicast could be the best way to overcome this drawback since it could let many hosts share one stream; however, its deployment on the Internet is still limited due to several fundamental concerns. CDN (Content Delivery Networking) can push the content and service to the edge of Internet by utilizing a set of service nodes that have been predeployed, thus alleviate the burden on the server and the network, but ICPs can not afford the expensive charge of CDN. P2P media streaming can utilize bandwidth resource of host nodes to provide service to other peer nodes without changing the current deployment of Internet; it is cost-effective and contains good application value in future.As the service capabilities of peer nodes are limited and heterogeneous, in additions these peer nodes can join or leave the system at any time, but media streaming is a special application type with stringent requirements, so there exist many challenging issues that need to be addressed in p2p media streaming, include how to search and choose the peer suppliers, how to deal with the leave or failure behaviors of peer nodes, how to guarantee peer nodes' QoS and how to deal with the heterogeneities of peer nodes and so on, these challenges actually constitute the key problems in peer-to-peer streaming media content distribution research area. The dissertation thoroughly studies these problems and gives some efficient proposals.First to large-scale VoD application environment, the dissertation proposes a new single multicast tree based P2P VoD service architecture—PeerVoD, in which each peer node has a fixed-size FIFO buffer to cache the most recent content of the video stream it receives, and can provide service to subsequent peer nodes. PeerVoD adopts a distributed multicast tree construction protocol, through maintaining a limited number of other peer nodes' states on each node, a new node can quickly find its parent in its joining process, and whenever a leave or failure occurs, each child node can also quickly find its new parent through its maintained state info. In PeerVoD, the leaves or failures of peer nodes can normally be recovered without affecting the server, and thus can relieve the server's load and make the architecture with good scalability. In additions, it considers the integrity of the received program in service recovering processes of interrupted nodes.As the service capabilities of peer nodes are limited, there always need multiple supplying peer nodes cooperate to serve a requesting node. Further more consider the heterogeneities of peer nodes, that is, they have different outbound/inbound bandwidth, and the media content they can provide is also different. Layered media streaming can adapt the...