Research Information System
Thesis Type: Postgraduate
Institution Of The Thesis: Gazi Üniversitesi, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2016
Student: BEKİR BORSUK
Supervisor: CEMAL KOÇAK
Open Archive Collection: AVESIS Open Access Collection
Abstract:With development of technology; mobile and wireless networks' coverage has extended and implementation became easier. As a result, their usage has increased. Hence, these developments also lead some problems. Due to inflation of interconnecting devices, data that flow through the network increases, on the other hand, performance of the network decreases. Therefore, multimedia applications, which relies on high Quality of service (QoS), widely effected by this deficiency. In addition, coverage and hidden node problems come up with freedom of movement which mobile and wireless networks provide. Collision detections and performance deficiencies occur as a result of hidden node problem. Thus, recent works in this area focus on decreasing the effects of performance deficiency. The results of previous studies show that, RTS values are effective on data transmission performance at RTS / CTS (Request to Send/ Clear to Send) mechanism in wireless networks. In this study, effects of RTS/CTS mechanism usage on transmission performance in case the absence or the presence of hidden node problem for multimedia applications at IEEE 802.11 MAC protocol revealed. No RTS and selected RTS values (as 1-200-400-800-1600-2346 bytes) scenarios are used. The values which used as scenarios are RTS threshold values. When data frames come larger than RTS, the RTS/CTS mechanism step in. By using Throughput, Retransmission Attempts, Packet Drop, Delay, Jitter and Traffic Received criteria, RTS/CTS mechanism's effects on network performance examined. Applications were simulated with 6 nodular structure over 14 different scenarios by using OPNET Modeler Simulation Tool. The results show that the RTS/CTS mechanism has improved performance.