19. Operation of AODV Route Discovery: Whenever a source node has to send information to a destination, but doesn’t have a valid route to it, it initiates a route discovery process. The source creates an AODV RREQ (Route Request) packet. This packet contains the source node’s IP address, current (source) sequence number, destination IP address, last known destination sequence number (set to zero if no prior route exists), a broadcast ID , which is incremented with each RREQ and a Hop Count field set to zero.
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26. Operation of AODV (cont..) Reverse Path Setup Forward Path Setup Fig. 2 Paths formed during the route discovery
27. Operation of AODV (cont..) Fig. 4.2.1 Propagation of RREQ Fig. 4.3.1 Route Maintenance and route determination