IJMIE Volume 5, Issue 1 ISSN: 2249-0558 _________________________________________________________ A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. International Journal of Management, IT and Engineering http://www.ijmra.us 105 January 2015 Comparative Study of Optimized Link State Routing Protocol Based on IPv4 and IPv6 Mohamed H. M. Nerma * Alaa Eldin A. Y. Abdalla ** Mohamed A. A. Elmaleeh *** * College of Engineering, School of Electronic Engineering, Sudan University of Science and Technology, Khartoum, Sudan ** Petro-Energy E&P Co., Ltd. Sudan *** Department of Electrical and Electronic Engineering, Khartoum, Sudan Abstract Mobile Ad-Hoc Network (MANET) is a wireless network without infrastructure. Nodes act as a router, client and server as well and its topology is dynamic as nodes join the network whenever there is need to transmit data and leave the network when transmission gets over. Optimized Link State Routing protocol (OLSR) is a proactive MANET routing protocol used in (MANET). In this paper the performance of OLSR protocol is evaluated and compared under IPv4 and IPv6 by considering the three different routing aspects: scalability, network load and mobility. File Transfer Protocol (FTP) and Transmission Control Protocol (TCP) traffics are used over the designed network. Performance metrics delay, routing overhead, and throughput are used for the performance analysis. OPNET Modeler 14.5 is used as a simulator. The simulation results show that by increasing the number of nodes the OLSR floods the network with a high amount of routing traffic in both protocols. In IPv4, it is found that the variation in the number of nodes and the network speeds do not significantly affect the performance of OLSR in terms of end-to-end delay and throughput, while in IPv6 it has a considerable affect.