Another in the family of routing protocols for mobile ad-hoc network is
on-demand routing protocols. With on-demand protocols, if a source node requires
a route to the destination for which it does not have route information, it
initiates a route discovery process which goes from one node to the other until
it reaches to the destination or an intermediate node has a route to the
destination.
It is the responsibility of the route request receiver node to reply back to
the source node about the possible route to the destination. The source node
uses this route for data transmission to the destination node. Some of the
better known on-demand protocols are Ad-hoc On-demand Distance Vector routing (AODV),
Dynamic Source Routing (DSR) and Temporary Ordered Routing Algorithm (TORA).
These protocols differ on storing the previously known route information and
on how they use the established route data. Again, in a network with many
participating nodes we may suffer with same sort of problems what we have seen
in table-driven protocols.
Conclusion
In conclusion, routing is one of the core issues in mobile ad-hoc network. An
effective routing mechanism will be helpful to extend the successful deployment
of mobile ad-hoc networks. Current routing protocols provide routing solutions
up to a certain level, but are lacking the ability to handle other related
issues.
Moreover most of these protocols have designed and implemented on small
scale. If these protocols could be extended further by taking into accounts
other routing related factors we may come out with a standard routing solution
for mobile ad-hoc network.
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