Wireless/mobility group

1. Wireless/mobility group Luís Rodrigues, Aline Viana, Roy Friedman, Daniela Gavidia, Spyros Voulgaris

2. What is specific about wireless/mobile settings? • Which gossip techniques designed for the wired setting can be applied to the w/m? • Which gossip techniques designed for the wired setting cannot be applied in the w/m setting? • What are the different classes of w/m systems?

3. Some classes of settings • Static networks • Networks with relatively “cheap” routing • DTNs-like networks • Connected dynamic networks with limited broadcast

4. Static networks • Sensor network • Ad hoc network with small relative mobility • Use structured approaches

5. “Cheap” routing • Assume routing exists • Gossip similar to the wired setting with a few twists: • Correlation between the overlay and the network is more important • Important to use biased gossip

6. DTNs-like networks • Network may be not connect • Becomes connected due to the movement of the nodes • Gossip always • No resource constraints • But you can plan node movements: message ferries • Selective gossip • Resource constrained • Use movement patterns to decide when to gossip

7. Connected dynamic networks with limited broadcast • Neighbors are not controlled by the gossip algorithm • Sources of dynamism • Movement • Power saving mode • Interference from the environment • Better to do the limited broadcast than keep track of exact membership of neighbors

8. Reverse gossip • All neighbors potentially receive the gossip • Recipients have to take local decisions (possibly using randomization) to decide if they act upon the gossip • Examples: • Pure probabilistic • Distance based approaches • Timer based approaches • Color based • Combinations of the above