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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
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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 & unpredictably
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
Hierarchical Forwarding • reduce complexity in individual node • scale to large number of nodes • Grid • Terminodes