Usually, in environments where infrastructure like routers and access points are absent, DSR enables efficient data packet routing by relying on the cooperation of individual nodes to relay messages to the intended destinations.
This protocol plays a crucial role in mobile ad hoc networks (MANETs), where network topology can frequently change due to node mobility, leading to the need for adaptive, efficient routing.
The accumulated path information is cached by nodes processing the route discovery packets.
Dynamic source routing protocol (DSR) is an on-demand protocol designed to restrict the bandwidth consumed by control packets in ad hoc wireless networks by eliminating the periodic table-update messages required in the table-driven approach.
The major difference between this and the other on-demand routing protocols is that it is beacon-less and hence does not require periodic hello packet (beacon) transmissions, which are used by a node to inform its neighbors of its presence.
Each Route Request carries a sequence number generated by the source node and the path it has traversed.
The intermediate nodes also utilize the route cache information efficiently to reduce the control overhead.
The disadvantage of this protocol is that the route maintenance mechanism does not locally repair a broken link.
Also, considerable routing overhead is involved due to the source-routing mechanism employed in DSR.