الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
In recent years, Internet technology has emerged as the major driving force behind new developments in the area of telecommunications networks. The volume of packet data traffic has increased at extreme rates. In order to meet these changing traffic patterns, more and more network operators adapt their strategies and plan to migrate to IP-based backbone networks. Clearly, the Internet will dominate our daily life in the future much more than today.
The success of emerging high-speed mobile integrated services network architectures will depend on their ability to arbitrate among various data sources with different quality of service (QoS) requirements over shared wireless links. As the traffic streams of the sources will have widely varying traffic characteristics, the air interfaces of wireless networks should have in common a high degree of flexibility and capacity, in order to support the very different traffic types.A well-designed packet reservation multiple access (PRMA) protocol, which is one of the best alternatives to be used as a media access control (MAC) protocol, has been geared toward using the voice activity detection to determine the maximum number of users which can be accommodated on the wireless channel.The PRMA protocol should provide an efficient mechanism to share the limited bandwidth resources and satisfy the diverse and usually contradictory QoS requirements of any traffic class (voice, video and data).In this thesis, we propose two new protocols that combine the advantages of distributed access and centralized control for transporting voice, Variable Bit Rate (VBR) and data traffic efficiently over General Packet Radio Service (GPRS) wireless channel. The first protocol is the basic PRMA with modification to support video and we study this protocol in three different cases according to the scenario of transmitting the data packets.But in the second protocol, we specify a constant number of channels for each traffic type.We simulate the data traffic as internet traffic (Web files). The design objectives include maximizing the system capacity and providing the required QoS to each user based on the traffic type.The obtained Results show that, the performance of GPRS measured in terms of system throughput, video and voice DROPping probability and the average data delay are more enthusiastic compared with the previous studies. Simulation results are presented to show that the protocol respects the required QoS of each traffic category while providing a highly efficient utilization of approximately 93% for the wireless GPRS channel.So mobile users can access to Internet and obtain data in short time.