الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
3GPP has started long term evolution (LTE) since 2004. The LTE
system provides higher data rate, lower delay, and improved coverage and
spectrum efficiency. With the characteristics of LTE, many creative
services, especially the multimedia services, which require more wireless
resource emerge.
We are currently witnessing an unbelievable technological
development; some may even say a breakthrough. Over the last decade,
there has been a rapid growth in the personal consumption of media.
Services like pay-per-view and video-on-demand are becoming more and
more common and are changing the way we look at multimedia – now users
can choose whatever media they want, whenever and wherever they want.
When we consider multimedia services (such as television or large file
downloads), we realize that the increasing traffic and congestion in the radio
spectrum caused by these can lead to degradation of the quality of service.
Many emerging applications are based upon a group communications model.
In particular, they require packet delivery from one or more authorized
senders to a large number of authorized receivers. In the Internet, multicast
has been used successfully to provide an efficient, best effort delivery
service to large groups. Securing group communications, i.e., providing
confidentiality, authenticity, and integrity of messages delivered between
group members, is a critical networking issue.
Another major issue is to update security keys (rekeying) when a user
joins or leaves the multicast group. For the rekeying of the group key all
members of the group should agree the rekeying of the key.
Abstract
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In this thesis, the performance of the Secure Multicast Overlay (SMO)
and the Group Security Association (GSA) is studied. We functionally
compare GSA with SMO in terms of data forwarding, Keys management
procedures and look up policies. The thesis presents a simulation model to
evaluate the performance of the two security solutions using MATLAB.
The present work is done for different values for number of traffic
flows (including changing population of users and users flow size) as well as
different values for the cluster size.
The obtained Results show the effect of these values on gateway
forwarding rate, router forwarding rate, number of gateway managed
security association, group setup rate, key request rate and rekeying rate.
Also the computational cost and storage cost for rekeying with and
without dynamic rekeying (during the changing of the height and degree of
the key tree for dynamic rekeying) will be calculated for the same used
values of the population of user and the user flow size.