1. Ant Rowstron Microsoft Research Cambridge, UK Joint work with Giovanni Pau (UCLA/sabbatical at MSRC) Wireless Workshop 31/7/20071

2. Question? A bottom of the range car comes with power ports, Bluetooth, USB ports and an IPod enabled stereo Why no 802.11 wireless? Cost? Technology? Applications? Platform? Wireless Workshop 31/7/20072

3. Technology evolution Simple simulation Advanced “realistic” simulation Emulation or small testbeds Running on large testbeds Running for real Wireless Workshop 31/7/20073 1 1 2 2 3 3 4 4 5 5 Easy Hard Algorithmic complexity increases Algorithmically complexity decreases Simple Algorithms

4. Map-assisted routing protocol Multi-hop routing protocol for vehicular networks Assumes each node has a digital map Exploits map to enable Routing Combines “junction-based source routing” with Greedy Routing Efficient node/service discovery Controlled exploration of the roads Related Work include GeoOpps, Trajectory Routing, MIRP Wireless Workshop 31/7/20074

5. Simple greedy routing Wireless Workshop 31/7/20075

6. Map-assisted source routing Exploit junctions Wireless Workshop 31/7/20076

7. Map-assisted source routing Wireless Workshop 31/7/20077 Packet: <Path: Victoria Road -> Garden Walk Go W Victoria Road -> Harvey Avenue Go W Victoria Road -> Frenchs Road Go SW > Packet: <Path: Victoria Road -> Garden Walk Go W Victoria Road -> Harvey Avenue Go W Victoria Road -> Frenchs Road Go N > Note: Packets greedily routed towards next junction.

8. Map-assisted discovery Exploit map topology to explore roads Captures car density

9. Thank you Wireless Workshop 31/7/20079