Dynamic Source Routing (DSR)
•When node S wants to send a packet to node D, but does not know a route to D, node S initiates a route discovery
•Source node S floods Route Request (RREQ)
•Each node appends own identifierwhen forwarding RREQ
Route Discovery in DSR
•Destination D on receiving the first RREQ, sends a Route Reply (RREP)
•RREP is sent on a route obtained by reversingthe route appended to received RREQ
•RREP includes the routefrom S to D on which RREQ was received by node D
•Node S on receiving RREP, caches the route included in the RREP
•When node S sends a data packet to D, the entire route is included in the packet header
–hence the name source routing
•Intermediate nodes use the source routeincluded in a packet to determine to whom a packet should be forwarded
•When node S wants to send a packet to node D, but does not know a route to D, node S initiates a route discovery
•Source node S floods Route Request (RREQ)
•Each node appends own identifierwhen forwarding RREQ
Route Discovery in DSR
•Destination D on receiving the first RREQ, sends a Route Reply (RREP)
•RREP is sent on a route obtained by reversingthe route appended to received RREQ
•RREP includes the routefrom S to D on which RREQ was received by node D
•Node S on receiving RREP, caches the route included in the RREP
•When node S sends a data packet to D, the entire route is included in the packet header
–hence the name source routing
•Intermediate nodes use the source routeincluded in a packet to determine to whom a packet should be forwarded
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