IPTV, an emerging Internet application,
would revolutionize the entertainment and media
industries; however, IPTV also has the potential
to overwhelm the Internet backbone and access
networks with traffic. To date, IPTV over P2P
streaming networks has advanced significantly
using two different approaches: tree-push versus
mesh-pull. In particular, the mesh-pull streaming
approach has achieved a number of successful
commercial deployments. In this article, we
examine the current progress in the research and
development of mesh-pull P2P streaming systems. We provide an overview of the general
mesh-pull streaming architecture and review various challenges, design issues, and interesting
research problems in this approach. We discuss
the construction costs for providing an IPTV service with service guarantees. We outline a measurement technique for monitoring the video
playback quality of mesh-pull streaming systems.
We emphasize that the future P2P IPTV systems
should be designed to meet the expectations of
users for quality-of-experience. We also identify a
few other important issues for IPTV over P2P
streaming networks, including the traffic pressure
on ISPs, various security concerns, and the necessity to re-examine the most appropriate P2P
architecture. Insights obtained in this study will
be valuable for the development and deployment
of future P2P IPTV systems.