This document discusses routing protocols for mobile ad-hoc networks (MANETs). It introduces several routing protocols including proactive (table-driven) protocols like Destination-Sequenced Distance Vector (DSDV), reactive (on-demand) protocols like Ad-hoc On-Demand Distance Vector (AODV) and Dynamic Source Routing (DSR), and hybrid protocols like Zone Routing Protocol (ZRP) that use both proactive and reactive approaches. For each protocol, it provides a brief overview of the routing approach and algorithm. It also compares the characteristics of proactive, reactive and hybrid routing protocols.

1. Routing in MANET

4. Ad-Hoc Development

5. MANET(Mobile Ad-Hoc Network) Features

6. MANET Application

7. MANET Issue

8. MANET Routing Protocol(1/2)

12. Distance-Vector MH3 MH2 MH4 MH6 MH5 MH8 MH7 MH1

16. Example of DSDV in operation MH 3 MH 6 MH 2 MH 1 MH 7 MH 4 MH 8 MH 5

17. Example of DSDV in operation MH 3 MH 6 MH 2 MH 1 MH 7 MH 4 MH 8 MH 5 MH 4 Forwarding table: Destination Next Hop Metric Seq. No MH 1 MH 2 2 S406_MH 4 MH 2 MH 2 1 S128_MH 1 MH 3 MH 2 2 S564_MH 2 MH 4 MH 4 0 S710_MH 3 MH 5 MH 6 2 S392_MH 5 MH 6 MH 6 1 S076_MH 6 MH 7 MH 6 2 S128_MH 7 MH 8 MH 6 3 S050_MH 8

19. Example of DSDV in operation MH 3 MH 6 MH 2 MH 7 MH 4 MH 8 MH 5 MH 1 MH 4 advertised table (updated): Destination Next Hop Metric Seq. No MH 1 MH 6 3 S516_MH 4 MH 2 MH 2 1 S238_MH 1 MH 3 MH 2 2 S674_MH 2 MH 4 MH 4 0 S820_MH 3 MH 5 MH 6 2 S502_MH 5 MH 6 MH 6 1 S186_MH 6 MH 7 MH 6 2 S238_MH 7 MH 8 MH 6 3 S160_MH 8

25. Unidirectional and Bi-directional links A B C D

30. AODV Features V.S. DSDV Routes are created only when required Each node doesn’t maintain all routes to other nodes (only active routes) Use of sequence numbers at each destination to maintain freshness of routing information( solve loop problem ) Reduces periodic broadcast Paths generated are loop-free Uses symmetric links (if a link is not symmetric it is not up) Works both on wired media and wireless media

33. Route Discovery(1/2) Unique Unique RREQ freshness Reverse freshness RREQ RREQ source_addr source_sequence_# broadcast_id dest_addr dest_Sequence_# hop_cnt

43. Route Discovery(2/13) Represents a node that has received RREQ for D from S B A S E F H J D C G I K Z Y M N L

46. Route Discovery(5/13) Represents transmission of RREQ Broadcast [S] [X,Y] Represents route record stored in RREQ B A S E F H J D C G I K Z Y M N L

48. Route Discovery(7/13) [S,E] [S,C] [S,B] B A S E F H J D C G I K Z Y M N L

51. Route Discovery(10/13) J and K both broadcast RREQ to D [S,C,G,K] [S,E,F,J] [S,B,H,I] [S,E,F,J,D] [S,C,G,K,D] B A S E F H J D C G I K Z Y M N L

52. Route Discovery(11/13) D does not forward RREQ, because D is the intended target [S,E,F,J,M] B A S E F H J D C G I K Z Y M N L

54. Route Discovery(13/13) RREP [S,E,F,J,D] Represents RREP control message B A S E F H J D C G I K Z Y M N L

56. Route Maintenance(2/6) B A S E F H J D C G I K Z Y M N L

58. Route Maintenance(4/6) Represents RERR message [S,E,F] B A S E F H J D C G I K Z Y M N L

60. Route Maintenance(6/6) [S,E,F,J,D] [S,C,G,K,D] B A S E F H J D C G I K Z Y M N L

61. DSR vs. AODV AODV DSR Path Information Limited information More detail Times of Route Discovery Many Few Traffic when RREP Low High Live time of route path New We don’t know Delete invalid path when RRER Delete all Only delete some node

63. Conclusion(1/2) Routing class Proactive Reactive Hybrid Routing structure Both Mostly flat Mostly hierarchical Availability of route Always available Determined when needed Depend on the location of the destination Control traffic volume High medium low Periodic updates Yes No Usually used inside each zone , or between gateways Handling effects of mobility Usually updates occur at fixed intervals. AODV,DSR uses local route discovery Usually more than one path maybe available. Single point of failures are reduced by working as a group

64. Conclusion(2/2) Routing class Proactive Reactive Hybrid Storage requirements High Depends on the number of routes kept or required. Usually lower than proactive protocols Usually depends on the size of each cluster or zone may become as large as proactive protocols if clusters are big Delay level Small routes are predetermined Higher than proactive For local destinations small. Inter-zone maybe as large as reactive protocols Scalability level Usually up to 100 nodes. Source routing protocols up to few hundred nodes. Designed for up to 1000 or more nodes