Simulation of the Enhanced Associativity Based Routing Protocol for Mobile Ad Hoc Networks (MANET)

: The simulations results showed that the overall EABR enhancement, when compared with ABR, in terms of communication overhead was ranging from 36% to 56%. While the overall EABR enhancement in terms of number of operation required to reconstructing the route was ranging from 36% to 55%. These enhancements were contributed to the novel way in route reconstructing introduced by EABR.


INTRODUCTION
In [2] a new method for route reconstruction for the ABR [1] was proposed. The routing table was amended with a Serial No field to enhance the optimization while reconstruction of the route. Three MH movements were covered, namely SRC, IN and DEST.
The route re-construction process makes use of the advantage of locality of neighbouring Mobile Hosts (MHs) to quickly construct alternate and even shorter routes, i.e. route optimization through using the Here I am packets.
In the original ABR the DEST role in route reconstruction was passive in the case of DEST movement, while in EABR the DEST has an active role in route reconstruction. Beside that, ABR route invalidation was always performed toward the DEST in the case of IN movement, while an optimization was achieved in EABR to invalidate the shortest partial route from the IN toward either the DEST or the SRC.
In [3] the communication and operation complexity analysis for two protocols namely the ABR and the EABR was presented. The operation complexity and communication complexity as defined in [1] were compared for both the ABR and the EABR, where the values represent the worst-case analysis.
The EABR proofed to be better in route reconstruction, which is attributed to the novel way in which the EABR reconstruct the route after movement of any node and the active role of the moved node in route reconstruction phase [3] .

Study of Communication Overhead: Network = 30 -50 Nodes -Route = 30 nodes
In this scenario the number of nodes, which constitute the route, are 30 while the number of nodes constitute the entire network are varying from 30 to 50. Different results were observed as shown in Figs. 1, 2, & 3.
The simulation results showed that the EABR enhancement in route reconstruction ranges from 36% to 41% under different topologies. In cases when the reconstruction is done in the first half of the route the enhancement ranges from 60% to 70% under the different topologies, while enhancement reached 11% when the reconstruction is done in the second half of the route. The communication statistics are summarized in Table 1. The simulation results showed that the EABR enhancement in route reconstruction ranges from 34% to 38% under different topologies. In cases when the reconstruction is done in the first half of the route the enhancement ranges from 62% to 72% under the different topologies, while enhancement reached 12% when the reconstruction is done in the second half of the route. The communication statistics are summarized in Table 2.  The simulation results showed that the EABR enhancement in route reconstruction ranges from 38% to 42% under different topologies. In cases when the reconstruction is done in the first half of the route the enhancement ranges from 66% to 76% under the different topologies, while enhancement reached 14% when the reconstruction is done in the second half of the route. The communication statistics are summarized in Table 3.  The simulation results showed that the EABR enhancement in route reconstruction ranges from 38% to 47% under different topologies. In cases when the reconstruction is done in the first half of the route the enhancement ranges from 66% to 80% under the different topologies, while enhancement reached 14% when the reconstruction is done in the second half of the route. The communication statistics are summarized in Table 4.  The simulation results showed that the EABR enhancement in route reconstruction ranges from 44% to 47% under different topologies. In cases when the reconstruction is done in the first half of the route the enhancement ranges from 76% to 84% under the different topologies, while enhancement reached 22% when the reconstruction is done in the second half of the route. The communication statistics are summarized in Table 5.  The simulation results showed that the EABR enhancement in route reconstruction ranges from 54% to 56% under different topologies. In cases when the reconstruction is done in the first half of the route the enhancement ranges from 84% to 90% under the different topologies, while enhancement reached 33% when the reconstruction is done in the second half of the route. The communication statistics are summarized in Table 6.   The simulation results showed that the EABR enhancement in route reconstruction reached 38% under different topologies. In cases when the reconstruction is done in the first half of the route the enhancement reached 68% under the different topologies, while enhancement reached 12% when the reconstruction is done in the second half of the route. The operation statistics are summarized in Table 8.  The simulation results showed that the EABR enhancement in route reconstruction reached 40% under different topologies. In cases when the reconstruction is done in the first half of the route the enhancement reached 72% under the different topologies, while enhancement reached 14% when the reconstruction is done in the second half of the route. The Operation statistics are summarized in Table 9.  The simulation results showed that the EABR enhancement in route reconstruction reached 45% under different topologies. In cases when the reconstruction is done in the first half of the route the enhancement reached 76% under the different topologies, while enhancement reached 18% when the reconstruction is done in the second half of the route. The Operation statistics are summarized in Table 10.  The simulation results showed that the EABR enhancement in route reconstruction reached 46% under different topologies. In cases when the reconstruction is done in the first half of the route the enhancement reached 81% under the different topologies, while enhancement reached 22% when the reconstruction is done in the second half of the route. The Operation statistics are summarized in Table 11.  The simulation results showed that the EABR enhancement in route reconstruction reached 55% under different topologies. In cases when the reconstruction is done in the first half of the route the enhancement reached 88% under the different topologies, while enhancement reached 33% when the reconstruction is done in the second half of the route. The Operation statistics are summarized in Table 12.

RESULTS AND DISCUSSION
The simulation study aimed to study the performance the EABR and original the ABR protocols in route reconstruction phase. The two factors used to conduct the simulation analysis between the protocols are: Operation Complexity and Communication Complexity as defined in [1] .
The study was restricted by the following assumptions in order to study the performance in route reconstruction phase only, no other cases were included in the study as it fails beyond the scope of our interest.

Operation complexity and Communication
Complexity as defined in [1] 2. Ideal environment i.e. no interference or noise signals 3.
A conference-sized network ranging from 30 to 50 nodes 4. 2 nodes can communicate/ respond with each other if they are in the transmission range 5. Nodes move in random manner 6. The route is already established The simulation strategy was based on measuring the communication overhead in terms of number of messages exchanged to perform a routing operation, and the Operation overhead in terms of the number of operations required to perform a protocol operation as defined in [1] .
Different topologies ranging from 30 to 50 nodes were used; also different route lengths ranging from 5 to 30 nodes were used in this simulation study.

CONCLUSION
1. The overall EABR enhancement in terms of communication overhead is ranging from 36% to 56%. 2. The overall EABR enhancement in terms of number of operation required to reconstruct the route is ranging from 36% to 55%. 3. The EABR communication enhancement in case the reconstruction point fail in the 1st half of the route is ranging from 60% to 90%. 4. The EABR communication enhancement in case the reconstruction point fail in the 2nd half of the route is ranging from 11% to 33%. 5. The EABR Operation enhancement in case the reconstruction point fail in the 1st half of the route is ranging from 66% to 88%. 6. The EABR Operation enhancement in case the reconstruction point fail in the 2nd half of the route is ranging from 11% to 33%. 7. In the backtracking process of the ABR, the process stops after reaching the node, which represent half of the hop count, which can be optimized more as there is a big possibility to have the destination to settle near to the upper part of the route. 8. When the network consists of relatively a large number of nodes and the established route consists of relatively small number of routes, the ABR is not efficient in route reconstruction, while the EABR is better in such topologies if compared to the ABR.