Routing Protocols
- 1. ROUTING PROTOCOLS IN MANETS By Rohit Sharma
- 2. WHAT IS A MANET Mobile nodes, wireless links Infrastructure-less: by the nodes, … Multi-hop routing: …, and for the nodes Minimal administration: no hassles
- 3. WHAT’S UNIQUE ABOUT A MANET ? Moving nodes ever changing topology Wireless links various and volatile link quality Pervasive (cheap) devices Power constraints Security Confidentiality, other attacks
- 4. CHALLENGES IN MANET ROUTING Need dynamic routing Frequent topological changes possible. Very different from dynamic routing in the Internet. Potential of network partitions. Routing overhead must be kept minimal Wireless low bandwidth Mobile low power Minimize # of routing control messages Minimize routing state at each node
- 5. MANET PROTOCOL ZOO Topology based routing Proactive approach, e.g., DSDV. Reactive approach, e.g., DSR, AODV, TORA. Hybrid approach, e.g., Cluster, ZRP.
- 6. ROUTING PROTOCOLS Reactive (On-demand) protocols Discover routes when needed Source-initiated route discovery Proactive protocols Traditional distributed shortest-path protocols Based on periodic updates. High routing overhead Hybrid protocols They introduces a hybrid model that combines reactive and proactive routing protocols.
- 7. REACTIVE ROUTING No routing structure created a priori. Let the structure emerge in response to a need Reactive routing is also known as on-demand routing protocol since they do not maintain routing information or routing activity at the network nodes if there is no communication. If a node want to send a packet to another node then this protocol searches for the route in an on-demand manner and establishes the connection in order to transmits and receive the packet. The route discovery occurs by flooding the route request packets throughout the network.
- 8. REACTIVE (ON-DEMAND) ROUTING: Routing only when needed 0 5 1 2 4 3 query(0) query(0) query(0) query(0) query(0) query(0) query(0) reply(0) reply(0) reply(0) Advantages: eliminate periodic updates adaptive to network dynamics Disadvantages: high flood-search overhead with mobility, distributed traffic high route acquisition latency
- 9. PROACTIVE ROUTING In proactive routing, each node has to maintain one or more tables to store routing information and any changes in network topology need to be reflected by propagating updates throughout the network in order to maintain a consistent network view.
- 10. HYBRID ROUTING They introduces a hybrid model that combines reactive and proactive routing protocols. The zone protocol (ZRP) is a hybrid routing protocol that divide the network into zones.
- 11. ZONE ROUTING PROTOCOL Zone 1 Zone 3 Zone 2