Journal of Computer Science 8 (7): 1134-1142, 2012
ISSN 1549-3636
© 2012 Science Publications
Corresponding Author: Alhamza Munther, National Advanced IPv6 centre of Excellence (NAv6), University Sains Malaysia,
11800 Penang, Malaysia
1134
Peer-to-Peer Video Conferencing
Using Hybrid Content Distribution Model
Alhamza Munther, Salah Noori, Azlan Osman,
Ayad Hussain, Imad Jasim and Ali Shanoon
National Advanced IPv6 Centre of Excellence (NAv6),
Universiti Sains Malaysia, 11800 Penang, Malaysia
Abstract: Problem statement: Multimedia Conferencing System (MCS) is a server-based video
conferencing system. One of the most critical limitations faced by this approach is the scalability issue.
In the MCS, the outgoing bandwidth of the server is shared among all concurrent clients. Thus, the more
clients there are, the lesser the bandwidth each client can have. The performance of this approach
therefore deteriorates rapidly as the number of simultaneous clients increases. In addition, a pure server-
based solution is expensive. Approach: In this research, the server-based infrastructure is modified into a
peer-to-peer video conferencing system while preserving the same functionality and features of the
existing MCS. This modification can be achieved using a hybrid content distribution model, which is a
combination of fluid and chunk content distribution models to distribute parts of the video stream fairly
among participants. The hybrid content distribution model offers a better way of handling heterogeneous
networks because it can distinguish between a fast peer and a slow peer, dealing with each one according
to its capabilities. Results: In our proposed system, the function server will not be used for video
distribution. Instead, it will only be used for monitoring and controlling the peers to reduce the burden on
the servers. Experimental results conducted in the nation advanced IPv6 center as a real environment and
live conferencing. Conclusion: This will lead to overcome the problem of scalability and a bandwidth
bottleneck on the main server and achieve good way to distribute video chunks.
Key words: Peer-to-peer, content distribution, heterogeneous network, widespread applications, video
conferencing system
INTRODUCTION
Video conferencing applications are scalability
issue limitation. Therefore, the overlay network is used
to overcome all other limitations through the utilization
of peer resources. An overlay network is a computer
network built on top of another network. Nodes in the
overlay are considered connected by virtual or logical
links each corresponding to a path, perhaps through
many physical links, in the underlying network
(Andersen et al., 2001). Three kinds of overlay
networks transfer the content parts: the Application
Layer Multicast (ALM) network similar to (Pendarakis
et al., 2001), the Peer-to-Peer (P2P) network such as
Napster (Saroiu et al., 2003) and the Content
Distribution Network (CDN) such as. Implementing
multicast functionality at the application layer of the
ALM network is feasible. CDN deploys servers in
multiple, geographically diverse locations distributed
over several Internet service providers. The client is
requesting for the content directly from the nearest
available server. P2P is an extremely popular method in
which nodes in the network, called peers, offer
resources such as bandwidth, processor and storing
capacity to other nodes. Consequently, as the number of
users increases, the global resources of the network also
grow. Peers that serve another peer can also be chosen
using proximity network criteria to avoid bottlenecks.
On the other hand, there are generally two types of
content distribution models as classified in (Saleh et al.,
2011): Fluid model and Chunk Content Distribution
model. Fluid model provides continuous transferring of
the content from the source to the multiple receivers
(Liu et al., 2003; Hossain et al., 2009). This model has
a tightly coupled connection (directly distributed bit by
bit continuously from source to destination) between
adjacent peers; therefore, it is considered as an optimal
distribution model to utilize bandwidth for fast peers
while causing congestion for slow peers. The second
type, Chunk content distribution model, chops the
content into equally sized pieces (called chunks) and
subsequently distributes each chunk. A peer not