الفهرس 
Mobile Ad hoc Network: characteristics, Challenges, Applications and Protocols
Implementation of the Proposed AlgorithmOnly 14 pages are availabe for public view
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Abstract
Resources in “Mobile Ad- hoc Network (MANET)” are scarce; therefore it is very important to reduce number of unimportant transmitted data packets and exchanged control packets among nodes, because each transmitted packet exhausts the battery power and needs processing capability at each node along its path. This could be done by diminishing number of control packets and reducing the number of nodes along the route between the originating and target node that reduce the number of transmissions. The control packets and power consumption of reactive protocols are less than proactive ones since routes are created solely when it is needed. As it being reactive protocol, “Ad hoc on Demand distance Vector (AODV)” still try to minimize the control packets at the expense of increased average end-to-end delay. The reasons for the delay to increase are due to the selection of long paths as a route, collision and congestion during path creation procedure.
This thesis revisits the issue of route discovery in “AODV” routing protocol, and forwards a proposal of an algorithm called Enhanced Route discovery Mechanism that suppresses non-optimal routes by identifying cases at which this non-optimal route is to occur during the route discovery process. The modified AODV with enhanced route discovery is called AODV_MOD. The first reason for the formation of non-optimal route is dropping of lately received Route Request (RREQs) by considering as if it has passed more hops than previously arrived. The algorithm, however, processes all RREQs that are received by nodes regardless of their arrival time and responds based on comparisons of their hop count. Besides, an increase in control overhead due to processing the same RREQ more than once is compensated by suppressing the initiation of Route Reply (RREP) which is unimportant and in addition has some contribution for the formation of non- optimal route even if the RREQ is received for the first time. By using this algorithm, the routing overhead and number of nodes in the source to destination path can be reduced. Ultimately, resulting in the reduction of the average end-to-end delay, number of packet re-transmissions, routing loads and number of data packets DROP between the originator and target node. As a result, the performance and efficiency of AODV routing protocol have been improved from point of view of packet delivery fraction, end-to-end delay and normalized routing load.