Vehicular Ad Hoc Networks VANETs Neil Tang 242009

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Vehicular Ad Hoc Networks (VANETs)Neil
Tang2/4/2009
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Outline

• Network Architecture
• Characteristics
• Applications
• Major Concerns
• 802.11p
• Network Layer Challenges
• Mobility Model

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Network Architecture
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Characteristics

• Multihop wireless network
• Mobile nodes with movements restricted by
  roadways
• Rich resources power, memory, processing
  capabilities.
• Every node is aware of its location, speed and
  moving direction.

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Applications

• Safety-related information dissemination
• Internet access for passengers

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Major Concerns

• Location-related broadcasting/multicasting
  support
• QoS support reliability and delay
• Scalability
• Cooperation
• Security

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802.11-based MAC Layer- 802.11p

• 5.9GHz licensed spectrum band
• High bandwidth
• Ad-hoc mode (hidden terminal problem)
• Short transmission range
• Poor mobility support

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Network Layer Challenges

• Traditional ad hoc routing VS. store-and-forward
  (stateless) routing
• Location-based unicast routing location is
  known.
• Geocast routing Location-related broadcast and
  multicast routing
• QoS support reliability and delay
• Mobility prediction Movements are restricted and
  mobility parameters are known.
• Routing in hybrid wireless networks (fixed
  roadside access points mobile node)

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Mobility Model

• The well-known random waypoint model is not
  suitable for VANETs.
• A mobility model needs to take into account the
  special movement properties Manhatten model and
  city section model