Gugrajah_Yuvaan_ Ramesh_2003.pdf
Gugrajah_Yuvaan_ Ramesh_2003.pdf
Gugrajah_Yuvaan_ Ramesh_2003.pdf
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Conclusion Chapter 6<br />
While the reactive protocols are able to cope better with mobility, there is a greater<br />
delay in providing routes due to the route request procedure that is only initiated<br />
when a route is required. Another disadvantage of reactive routing is that the entire<br />
network needs to be searched before a route is found, which makes the route<br />
discovery procedure very costly. The inclusion of route caches for nodes using<br />
reactive protocols could be useful, but the disadvantage is that stale routes represent<br />
a liability that may degrade performance rather than improve it.<br />
Various modifications have been made to the basic reactive and proactive routing<br />
protocols, which include special adaptations that are unique to ad hoc networking.<br />
By using physical layer properties such as signal quality and spatial properties such<br />
as mobility prediction, routes can be chosen such that they are more reliable, with the<br />
cost of the route request procedure being decreased.<br />
Hybrid varieties of the proactive and reactive routing protocols employ the table<br />
driven approach locally and the on demand approach globally, thereby attempting to<br />
exploit the advantages of both classifications of routing. The hierarchical routing<br />
protocols attempt to mimic the fixed infrastructure of cellular networks, with the aim<br />
of simplifying medium access control, code assignment, and routing functions.<br />
However selected nodes become overburdened and resources are consumed unfairly<br />
in the network<br />
All the routing protocols have advantages and disadvantages, and the particular<br />
application for the ad hoc network would determine what type of routing protocol to<br />
implement and whether or not higher cost and greater computational complexity can<br />
be justified.<br />
This dissertation proposes a new routing protocol based on DLAR [GerlaOO], which<br />
is a load balancing routing protocol. The new routing protocol, referred to as DLAR<br />
4 is unique because it combines load balancing with signal quality determination,<br />
which allows the routes selected to be of better quality, hence providing higher<br />
throughput. Simulations are used to compare the protocol to the original DLAR<br />
schemes and to another prominent reactive routing protocol, AODV [Perkins99].<br />
6-2
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