Abstract
There have been tremendous efforts and many
technical innovations in supporting real-time video streaming
in the past two decades, but cost-effective large-scale video
broadcast has remained an elusive goal. IP multicast represented
the earlier attempt to tackle this problem, but failed largely due
to concerns regarding scalability, deployment, and support for
higher level functionality. Recently, peer-to-peer based broadcast
has emerged as a promising technique, which has been shown to
be cost effective and easy to deploy. This new paradigm brings a
number of unique advantages such as scalability, resilience and
also effectiveness in coping with dynamics and heterogeneity.
While peer-to-peer applications such as file download and voice
over IP have gained tremendous popularity, video broadcast
is still in its early stages and its full potential remains to be
seen. This article reviews the state-of-the-art of peer-to-peer
Internet video broadcast technologies. We describe the basic
taxonomy of peer-to-peer broadcast and summarize the major
issues associated with the design of broadcast overlays. We closely
examine two approaches, namely, tree-based and data-driven, and
discuss their fundamental trade-off and potential for large-scale
deployment. Finally, we outline the key challenges and open
problems, and highlight possible avenues for future directions.
