Proximitybased Group Communication

1
Proximity-based Group Communication

• Vinny Cahill
• vinny.cahill_at_cs.tcd.ie

Distributed Systems Group Trinity College Dublin
2
Sentient Traffic Management

• Group membership determined by proximity
  constraints
• e.g. obstalce warning system

3
Issues

• Group membership often depends on location
• Very dynamic groups
• Difficult to differentiate between the failure of
  a host and its movement out of network coverage
• Network partitions are expected!
• Network topology changes frequently due to
  mobility
• Variable round-trip times make predictable
  behaviour difficult

4
Proximity-based Group Communication
A Proximity group G is defined by its name
reference point, shape, and navel G Name,
Reference Point, Shape, Navel
Traffic light Shape circle of radius 100m Ref.
Point 10m left of centre Navel traffic light
Ambulance Shape circle of radius 100m Ref.Point
centre Navel ambulance car
5
Proximity-based Group Communication
Ordered, reliable, and timely group communication
Group membership management
Partition anticipation
Coverage awareness
Routing/Geocasting
Connectivity awareness
Location awareness