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Supporting Video-on-Demand (VoD) services in Internet is still a
challenging issue due to high bandwidth requirement of multimedia contents
and additional constraints imposed by such environment: higher delays and
jitter, network congestion, non-symmetrical clients’ bandwidth and inadequate
support for multicast communications. This paper presents DynaPeer, a peer-topeer
VoD delivery policy designed for Internet environment. Our design defines
a Virtual Server, which is responsible for establishing a group of peers,
enabling service for new client requests by aggregating the necessary clients’
resources. Virtual Server operates in both unicast and multicast environments,
thereby improving system performance. To demonstrate the effectiveness of
DynaPeer, we have developed an analytical model to evaluate its performance,
understood as the server-load reduction due to request service distributed
among peers. We conducted a performance comparison study of our proposal
with classic unicast, multicast (Patching) and other P2P delivery schemes, such
as Pn2Pm, Chaining and Promise, improving their performance by 45%, 59%,
74% respectively, even when taking into account Internet constraints.
This research is supported by the MEyC-Spain under contract TIN 2004-03388. |