Abstract: All wireless cellular networks suffer with reliability issue which is directly connected with the Transport Layer Protocols, and also selection of proper Transmission Ranges for the Base Stations. In this paper we study through extensive simulation scenarios, the effects of Transmission Range of BSs for two prominent Transport Layer Protocols- Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) respectively over mobile WiMAX networks. The NIST WiMAX module is used to configure WiMAX environment in NS-2. The QoS metrics used to evaluate the performance are Packet Delivery Ratio (PDR), Throughput, Normalized Routing Overhead (NROH) and Average End to End Delay. Simulation results reveal that performance increases with increasing the transmission range of the BSs up to a certain range, after that range it degrades. Throughputs are almost similar for both TCP and UDP but TCP shows more stability and its reliability may prefer it for most of the applications.

Keywords: Mobile WiMAX, TCP, TCP New Reno, Transmission Range, Transport Layer Protocols, UDP.