1. MAP BASED ROUTING IN LARGE SCALE URBAN VEHICLE NETWORKS

2. AGENDA

3. OPTIMAL ROUTING ALGORITHM  Minimum Delay Algorithm (MDA)  Minimum Delay and Hops Algorithm (MDHA)  Vehicular to Vehicular, Vehicular to Location, Location to Location

4. INEFFICIENCY OF EXISTING ALGORITHMS REVEALED  Geo routing family:  Performance degrades quickly as transmission distance increases  Local maximum is extremely hard to detect  Mobility based routing family  Is the behavior of individual node really RELAIBALY predictable?  Choice of the length of time frame used in statistical pattern mining  Let’s consider the JOINT probability

5. AN EXAMPLE

6. PROPERTIES OF OPTIMAL ROUTING PATH  Relative spatial stability  Relative temporal stability  Routing sequence is very dynamic

7. MAP BASED ROUTING  Switch the respective ItemFromTo nodevehicles intersectio ns linkcontactsroads Weighted by Signal quality Average packet travel time

8. MODEL FOR A ROAD SECTION  Modeled as a bi-directed link  The weight of a link reflects the average packet travel time over that link

9. ALGORITHM ENHANCEMENT

10. PERFORMANCE  Comm radius 100m, transmission distance 6KM

11. FACTOR － COMM RANGE