The performance of mobile ad-hoc networks
(MANET) is related to the efficiency of the routing protocols in
adapting to frequently changing network topology and link
status. This paper addresses the issue by comparing the
relative performance of three key ad-hoc routing protocols:
Destination-sequenced Distance Vector (DSDV), Ad-hoc Ondemand
Distance Vector (AODV) and Optimized Link State
Routing (OLSR). The protocols are tested based on two
scenarios, namely, tactical networks for ships and sensor-based
network nodes. Four performance metrics were measured by
varying the maximum speed of mobile hosts, network size and
traffic load, to assess the routing capability and protocol
efficiency. The simulation results indicate that AODV
performs better than OSLR and DSDV in the first scenario.
Although OLSR also performed relatively well, the associated
high routing overhead is the dominant reason for not choosing
it. On the other hand, OLSR emerged as the protocol of choice
for sensor networks, where the high routing overhead is
counteracted by consistently better performance in all other
metrics. Due to the slow evolution of the sensor network
topology, OLSR performed satisfactorily for best effort traffic
but needed subtle adjustments to balance between latency and
bandwidth to meet the requirements of delay-sensitive
applications