ISSN 2277-3061 2691 | Page Nov 01, 2013 Mobility Impact on MANET Routing Protocols In Grid Networks Zeinab R. Khaleel,and Mahmoud M.AL-Quzwini College of Engineering, Alnahrain University, Baghdad, Iraq Department of Computer Engineering Abstract Mobile Ad-Hoc Networks (MANETS) is a collection of wireless mobile nodes that are able to dynamically form a temporary network without any aid from fixed infrastructure or centralized administration due to no wired backbone.Ad Hoc networks are formed spontaneously and the nodes are highly mobile.Thispaper presents performance evaluations, comparisons, andanalysis for three routing protocols (AODV, DSR, and OLSR) to bring out their relative meritsundervarying network size and mobilitywith various speed and pause times. The simulation is carried out using OMNET++ simulator based on the quantitative basic parameters like throughput, Packet transmission Ratio (PTR),packet transmission time delay and protocol overhead .The nodes are distributed randomly in a grid network topology and mobile nodes moving using Random Waypoint mobility models. The results demonstrate that, undervarious node speeds and pause timesfor different network size, AODVoutperforms DSR and OLSR protocols with respect to networkthroughput (by 0.9% and 4.4%, respectively). For protocoloverhead,DSR is about 13.4% and 65.5% below AODV and OLSR protocols respectively. In contrast, thepacket transmission time delay when using OLSR is shorter than whenusing both AODV (by 81.7%) and DSR (by 76.7%). Keywords ــ ــ ـMANET; AODV; DSR; OLSR. Council for Innovative Research Peer Review Research Publishing System Journal: INTERNATIONAL JOURNAL OF COMPUTERS & TECHNOLOGY Vol 11, No. 6 editor@cirworld.com www.cirworld.com , member.cirworld.com