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CSE 6007 Mobile Ad Hoc Wireless Networks. Unit II Topic 8-15 Routing Protocols for Ad Hoc Wireless Networks Department of Computer Science and Engineering Kalasalingam University. Outline. Introduction Topic 8 : Issues in Designing A Routing Protocol for Ad Hoc
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CSE 6007 Mobile Ad Hoc Wireless Networks Unit II Topic 8-15 Routing Protocols for Ad Hoc Wireless Networks Department of Computer Science and Engineering Kalasalingam University
Outline • Introduction • Topic 8 : Issues in Designing A Routing Protocol for Ad Hoc Wireless Networks • Topic 9 : Classification of Routing Protocols • Topic 10 : Table Driven Routing Protocols • Topic 11 : On-Demand Routing Protocols • Topic 12 : Hybrid Routing Protocols • Topic 13 : Routing Protocols with Efficient Flooding Mechnisms • Topic 14 : Hierarchical Routing Protocol • Topic 15 : Power Aware Routing Protocol
The main routing problems for MANETs 8 10 9 7 4 6 Node mobility Routing path broken frequently 2 3 5 1
Table-driven routing protocol – DSDV (cont.) Example: Routing table for Node 1 15 14 13 11 12 9 10 8 6 4 7 5 3 1 2
Table-driven routing protocol – DSDV (cont.) Routing table for Node 1 15 14 13 11 12 10 8 9 6 4 7 5 3 1 2
Route Discovery in DSR Y Z S E F B C M L J A G H D K I N Represents a node that has received RREQ for D from S
Route Discovery in DSR Y Broadcast Z [S] S E F B C M L J A G H D K I N Represents transmission of RREQ [X,Y] Represents route record stored in RREQ
Route Discovery in DSR Y Z S [S,E] E F [S,B] B C M L J A G [S,C] H D K I N • Node H receives packet RREQ from two neighbors: • potential for collision
Route Discovery in DSR Y Z S E F [S,E,F] B C M L [S,B,A] J A G [S,B,H] H D K [S,C,G] I N • C receives RREQ from G and H, but does not forward • it again, because C has already forwarded RREQ once
Route Discovery in DSR Y Z S E F [S,E,F,J] B C M L J A G H D [S,B,H,I] K I N [S,C,G,K] J and K both broadcast RREQ to D Theirtransmissions may collide at D
Route Discovery in DSR Y Z S E [S,E,F,J,M] F B C M L J A G H D K I N Ddoes not forward RREQ, because D is the intended target
Route Reply in DSR Y Z S RREP [S,E,F,J,D] E F B C M L J A G H D K I N Represents RREP control message
Y Z RERR [J-D] S E F B C M L J A G H D K I N An Example of Route Maintenance Route Error Packet : RERR J sends a route error to S along route J-F-E-S when it finds link [J-D] broken Nodes hearing RERR update their route cache to remove all invalid routes related with link J-D
[S,E,F,J,D] [E,F,J,D] S E [F,J,D],[F,E,S] F B [J,F,E,S] C M L [G,C,S] J A G [C,S] H D K [K,G,C,S] I N RREP RREQ Z Use of Route CachingCan Speed up Route Discovery When node Z sends a route request for node C, node K sends back a route reply [Z,K,G,C] to node Z using a locally cached route