Pull-based P2P live streaming is a promising solution for the large scale streaming systems, like PPStream, PPlive, due to its high scalability, low cost and high resilience. However, they usually suffer from bad dela...Pull-based P2P live streaming is a promising solution for the large scale streaming systems, like PPStream, PPlive, due to its high scalability, low cost and high resilience. However, they usually suffer from bad delay performance. In this paper, we seek to improve the delay performance under ensuring video display quality stemming from chunk scheduling. And so we model Pull-based chunk scheduling problem as a multi-objective optimization problem to minimize the video delay and maximize video display quality in the environment of heterogeneous upload bandwidths, heterogeneous and dynamic propagation delays. Finally we put up with a greedy Pull-based scheduling approach(GPSA) to solve the optimization problem. The evaluation shows GPSA can outperform two classical chunk scheduling approaches and adapt to dynamic variance of propagation delays.展开更多
Recent development of the peer-to-peer （P2P） live streaming technique has brought unprecedented new momentum to the Internet with the characters of effective, scalable, and low cost. However, before these applicatio...Recent development of the peer-to-peer （P2P） live streaming technique has brought unprecedented new momentum to the Internet with the characters of effective, scalable, and low cost. However, before these applications can be successfully deployed as commercial applications, efficient access control mechanisms are needed. This work based on earlier research of the secure streaming architecture in Trust- Stream, analyzes how to ensure that only authorized users can access the original media in the P2P live streaming system by adopting a user authentication and key management scheme. The major features of this system include （1） the management server issues each authorized user a unique public key certificate, （2） the one-way hash chain extends the certificate＇s lifetime, （3） the original media is encrypted by the session key and delivered to the communication group, and （4） the session key is periodically updated and distributed with the media. Finally, analyses and test results show that scheme provides a secure, scalable, reliable, and efficient access control solution for P2P live streaming systems.展开更多
基金supported by National Key Basic Research Program of China(973 Program)(2009CB320504)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (Grant No. 60821001)+1 种基金Beijing Municipal Commission of Education to build the project special,Research Fund for the Doctoral Program of Higher Education of China (20090005120012)National Natural Science Foundation (60672121)
文摘Pull-based P2P live streaming is a promising solution for the large scale streaming systems, like PPStream, PPlive, due to its high scalability, low cost and high resilience. However, they usually suffer from bad delay performance. In this paper, we seek to improve the delay performance under ensuring video display quality stemming from chunk scheduling. And so we model Pull-based chunk scheduling problem as a multi-objective optimization problem to minimize the video delay and maximize video display quality in the environment of heterogeneous upload bandwidths, heterogeneous and dynamic propagation delays. Finally we put up with a greedy Pull-based scheduling approach(GPSA) to solve the optimization problem. The evaluation shows GPSA can outperform two classical chunk scheduling approaches and adapt to dynamic variance of propagation delays.
基金Supported by the National Natural Science Foundation of China(No.60673184)the National High-Tech Research and Development(973) Program of China(No.2007AA01Z419)+1 种基金the National Basic Research(863) Program of China(No.2008CB317101)Tsinghua-ChinaCache CDN Program
文摘Recent development of the peer-to-peer （P2P） live streaming technique has brought unprecedented new momentum to the Internet with the characters of effective, scalable, and low cost. However, before these applications can be successfully deployed as commercial applications, efficient access control mechanisms are needed. This work based on earlier research of the secure streaming architecture in Trust- Stream, analyzes how to ensure that only authorized users can access the original media in the P2P live streaming system by adopting a user authentication and key management scheme. The major features of this system include （1） the management server issues each authorized user a unique public key certificate, （2） the one-way hash chain extends the certificate＇s lifetime, （3） the original media is encrypted by the session key and delivered to the communication group, and （4） the session key is periodically updated and distributed with the media. Finally, analyses and test results show that scheme provides a secure, scalable, reliable, and efficient access control solution for P2P live streaming systems.
