Understanding Topology Evolving of VANETs from Taxi Traces

Routing through Connected Components (CC) of VANETs is proved to be much more efficient than carry-and-forward strategies. Understanding the topology evolving features especially those relevant to CCs is very important for routing protocol design and algorithm optimization. This paper explores the network topology and its dynamics based on two real taxi-trace datasets. The size variance of the CCs are analyzed. Considering the time evolution, the stability and variation of the CCs are also examined. Together with the results for topology analysis, implications for routing protocol design and open research issues are then addressed.