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Scalable Routing In MANET. Yang Peng Supervisor: Dr. Yow Kin Choong. Scalability of ad hoc network. Main problems: Limited bandwidth Large number of nodes Mobility of network. Three Categories . Flat routing protocols Hierarchical routing protocols
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Scalable Routing In MANET Yang Peng Supervisor: Dr. Yow Kin Choong
Scalability of ad hoc network Main problems: Limited bandwidth Large number of nodes Mobility of network
Three Categories Flat routing protocols Hierarchical routing protocols Location-based routing protocols
Flat routing protocols Two categories: Proactive (table-driven) Reactive (on-demand)
Proactive protocols • FSR (Fisheye State Routing) • FSLS* (Fuzzy Sighted Link State) • OLSR (Optimized Link State Routing) • TBRPF (Topology Broadcast Based on Reverse Path Forwarding) • others
Scalability of proactive protocols • Large routing table when population of network is large • Large flooding of routing information when population of network is large • Frequent updating when mobility is high Only suitable for network with small population
Reactive Routing Protocols • AODV (Ad Hoc On-demand Distance Vector routing) • DSR (Dynamic Source Routing) • TORA (Temporally-Ordered Routing Algorithm) • Others
Scalability of reactive protocols • Because operations react to communication needs, overhead is relative to discovery and maintenance • Light traffic is needed when the number of route request is small Suitable for large network only when few route requests are generated.
Hierarchical Routing Protocols • When the network size increases, the flat routing schemes become infeasible because of link and processing overhead, hierarchical routing protocols are developed • Hierarchical routing: partition the network into groups and assign nodes different functionalities inside and outside a group”
Hierarchical Routing Protocols • CGSR (Clusterhead-Gateway Switch Routing) • HSR (Hierarchical State Routing) • ZRP (Zone Routing Protocol) • LANMAR (Landmark Ad Hoc Routing Protocol) • others
Scalability of hierarchical protocols Advantages • Every node maintains the link state information within the group, the routing table is scalable. • Only communications react between leaders of groups, overhead of routing processing is reduced. Problems • Efficient partition of network(reduce overlap) • Partition updating in groups when nodes move • Overhead of routing between groups
Location-based Routing Protocols • Aided by GPS • Every node has location information • Universal time is provided by the aid of GPS • Use geographical forwarding to send packets
Location-based protocols • 1.LAR (Location-Aided Routing) • 2.DREAM (Distance Routing Effect Algorithm for Mobility) • 3.GPSR (Greedy Perimeter Stateless Routing) • 4.GLS(Grid Location Service) • others
Scalability of location-based Advantages • Because of flooding directionally,flooding is reduced • Routing is more efficient and scalable than flooding undirectionally. Problems • Overhead of location information updating • Overhead of location and address mapping,a big table is need to maintain the mapping.
Conclusion • Flat routing protocol : It is not scalable for overhead of link state and processing. • Location-based routing protocol: updating of location information is flooded over the whole network.When mobility of network is high, it doesn't scale well. • Hierarchical routing protocol:Partition updating is maintained in local partition, so it scales better when mobility of network is high.
Modification of Hierarchical Routing Protocols(more scalable) • Partition of network: partition the network into groups by the aid of GPS, every group has fixed location and area and overlap of groups is reduced, then it is more scalable. • Partition updating: in a group when link to a leader is broken, repair it and make the group more stable, then overhead of partition updating is reduced. • Routing between groups:After partitioned by aid of GPS, every group has a location, use geographic forwarding to send packets directionally between different groups. Overhead of routing between groups is reduced, then it is more scalable.