Gugrajah_Yuvaan_ Ramesh_2003.pdf

Simulation ofa Load Balancing Routing Protocol
Figure 3-1. Example topology resulting in network congestion due to shortest
path routing.
Chapter 3
An aim of the research described herein was therefore to evaluate a routing protocol
that would perform load balancing in order to ensure that congestion in the network
would be avoided. Table-driven routing protocols were not considered suitable
because the mobility of the ad hoc network results in unnecessary overhead being
created due to table updates. Hierarchical, zone and cluster based schemes were
avoided because the aim was to treat all nodes equally and in these types of routing
protocols selected nodes tend to use more resources than other nodes when
maintaining local information. The aim was also to avoid periodic beaconing to
conserve power.
Dynamic Load Aware Routing (DLAR) [GerlaOO] is an on-demand routing protocol
that takes load balancing into account by determining the state of the buffers of
nodes along possible routes. DLAR has three original schemes, each differing in the
manner in which the buffer contents are evaluated for route selection. This chapter
discusses the modifications made to DLAR to iNclude a fourth scheme that also takes
into consideration expected signal quality and the signal to interference ratio (SIR)
along the route. Although SSR (described in Section 2.2.3.2) also takes into
consideration signal quality, the DLAR implementation proposed herein avoids the
periodic beacons of SSR and allows adaptive route selection from multiple possible
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