AODV: Route Maintenance
n if path breaks (hello messages, link-layer
acknowledgements), upstream nodes propagate unsolicited
RREP with higher sequence number and hop count of ¥ to
all active upstream nodes
n according to protocol, these RREPs get forwarded to other
active nodes, eventually all active correspondents will be
informed of link failure
n if needed, correspondents can start establishment of new
route by issuing RREQ with destination sequence number
one higher than last known sequence number
problem: how to make “smart” decision as to whether route is still
needed?