A Survey on Position-Based Routing in
Mobile Ad Hoc Networks
by Martin Mauve, Jorg Widmer, and Hannes
Hartenstein
Ad Hoc Networks Reviews
• Self-organizing
• No pre-established infrastructure
• Consisting of autonomous nodes
end systems as well as routers at the
same time
• Classification:
• Static – such as rooftop networks
• Mobile
• changing topology frequently &
Two different approaches in routing
• Topology-based routing
• proactive approaches
• reactive approaches
• hybrid approaches
• Position-based routing
Topology-based Approaches
Proactive routing protocols
- maintain routing info. of all available paths
Drawback: maintenance of unused path
Reactive routing protocols
- only maintain routes currently in use
Drawbacks:
- require route discovery
- suffer traffic increasing when topology change
- packets lost due to route changing
Topology-based Approaches (cont.)
Hybrid ad hoc routing protocols
-Zone Routing Protocol (ZRP): local proactive
routing with global reactive routing
Limitation: still need to maintain routes
currently in use
Position-based Routing Algorithms
• require physical location info of nodes
• routing decision: based on destination’s
location and locations of forwarding node’s
neighbors
• no establishment or maintenance of routes
Basic Principles and Problems
• location service: determine position of a node
- how many nodes host the service
- some or all nodes maintained by position
server
• forwarding strategies
- greedy forwarding
- restricted directional flooding
- hierarchical
Location Services
• Centralized approaches: viable only as an external
service that can be reached via non-ad hoc means
- single point of failure
- bottleneck on central server
- server might be far from nearby nodes
Example: cellular phone system
Location Services (cont.)
• Decentralized approaches: location service is
part of the ad hoc network
- Distance Routing Effect Algorithm for Mobility
(DREAM)
- Quorum-Based Location Service
- Grid Location Service
- Homezone
Example: Grid Location Service (GLS)
• hierarchy of squares
• n-order squares contain exactly four (n-1)order squares
• each node maintains all other node within the
local 0-order square
Forwarding Strategies: Greedy
- Most Forward within r (MFR)
- Nearest with forward progress (NFP)
- Compass routing
- Random choice with progress
Greedy routing failure & recovery
Restricted Directional Flooding
Hierarchical Forwarding
• reduce complexity in individual node
• scale to large number of nodes
• Grid
• Terminodes