Performance Comparison of Modified AODV-ETX with AODV and AODV-ETX Routing Protocol in an MANET

Abstract

Expected Transmission Count (ETX) is one of the many metrics developed in the ad hoc routing protocol. Most research, studied on modified AODV-ETX by varying the value of MY ROUTE TIMEOUT (MRT) and ACTIVE ROUTE TIMEOUT (ART) values in the RREQ and RREP packet headers. Those studies resulted the optimum value of MRT and ART was 80 seconds. These results has not shown optimal performance of AODV and AODV-ETX. This paper discusses performance comparison of modified AODV-ETX with AODV and AODV-ETX on MANET. The result is that the throughput on the modified AODV-ETX has increases 5.72 %, PDR increases 5.80 %, 4.31 % overhead reduction, 10.19 % increase on end to end delay, and 3.09 % increase on route discovery process.

Optimization in the Ad Hoc On-Demand Distance Vector Routing Protocol

“…countðt − ϑ, tÞ is the number of LPP received during the monitored window, and ϑ is the number of LPP, to be accepted. The value is determined as w = 10τ, and for τ, the value is τ = 1 s [26]. ETX requires both p f and p r .…”

“…This allows each neighboring node to calculate a value of p f to node X whenever a neighboring node receives an LPP from node X. The route metric is then the sum of the ETX values of each of the lines in the route [19]: [26]. With these values for each neighboring node, the node can calculate the ETX metric for its neighbor at any time In order for AODV to work with ETX metrics, ETX fields must be added to the protocol.…”

“…The best path is the one that has the smallest ETX metric. If multiple paths are found that have the same metric, then the one that has the fewest jumps to the target node is selected [26].…”

“…As soon as the RREQ message is forwarded to the target node, the ETX metric is updated for each node based on Equation (3). The same procedure applies to the management of the RREP [26].…”

“…The calculated ETX value using Equation (1) and 104 is multiplied and rounded to the integer value. This will ensure that the ETX metrics work properly in Network Simulator 3 [26].…”