Distributed cache updating algorithm for the dynamic source routing protocol
The accumulated path information is cached by nodes processing the route discovery packets. To accomplish source routing, the routed packets contain the address of each device the packet will traverse.This may result in high overhead for long paths or large addresses, like IPv6.To avoid using source routing, DSR optionally defines a flow id option that allows packets to be forwarded on a hop-by-hop basis.This protocol is truly based on source routing whereby all the routing information is maintained (continually updated) at mobile nodes.
Network administrators may delegate authority over sub-domains of their allocated name space to other name servers.Hence all neighbours replace the stale route in their cache.Experimental evaluation is done using network simulator (NS2) of monarch group.In conventional approach only the nodes involved in the routing path knows about the route error and those node only update their cache.But in U-DSR, by following distributed cache replacement algorithm, source node broadcasts the route error information of size 60 bytes to all its neighbours.
The route caching plays significant role in on-demand routing protocol to improve the Quality of Service (Qo S).