Research Article

The Improved Overhearing Backup AODV Protocol in MANET

Table 1

Comparison of discussed methods.

ScholarProtocolsFeaturesAdvantagesDisadvantages

Lai et al. [5]AODV-BRIt will not try to repair the broken path, so it will need lesser hops. There is expiration time possibility.Low delay: it needs less hops.Low throughput: if the speed goes high, the backup routes that had been made in reply phase will fail.

Lai et al. [5]AODV-LRIt uses local repair.It has a better throughput rather than BR and ABR and also has a wide repair searching range. It has more hops and high delay (because of increment in the path hops).

Lai et al. [5]AODV-ABRIf it detects a link failure then a handshake process will be used. AODV-BR has hop control signals such as BRRQ and BRRP. It can select a backup route. It is adaptive towards network topology. It has less control overhead and less delay than AODV-LR. It avoids collision and congestion issues. It has average throughput (less than LR and more than BR).

Lai et al. [5],
Zhou and Li [8]
AODV-ABLIt is an adaptive backup routing protocol which uses local repair. It works in a promiscuous mode (overhear the packets). This method has main and alternative routes.It has BRRQ and BRRP. The packet delivery ratio is high. It has a MAX_Repair_TTL threshold.It is possible to drop some alternative routes only with one hop distance to thedestination. It cannot update the main route in time to adjust with dynamic topology. There are a lot of hop counts. It has control overhead and throughput is almost low.

Zhou and Li [8]AODV-BFABLIt merges the main routes with alternative ones. It can update the routes during the data transmission. It is suitable for bidirectional traffics and is based on ABL.It improves adaptability. The packet delivery ratio is higher than ABL. Its delay and overhead are lower than ABL. It can avoid link failure with one hop distance to destination by packet overhearing.ā€”

Patil et al. [7]AR-AODVIt has two route replies. Also it has a local repair scheme and is able to dominate link failure.It improves the packet delivery ratio, protocol operations, and mobility. It reduces routing load and end-to-end delay. ā€”