Just recently, I noticed the term of Cyber-Physical-System, which matches well my understanding of VANET as a functional network.
The study of VANET distinguishes itself from the research of other communication systems by the fact that the vehicular communication serves as the means of realizing a physical function system, e.g. danger warning for vehicle drivers and cooperative driving. In such a system, each vehicle is an information source as well as an information sink that is organized into a system towards a target function. In this kind of systems, the communication is more closely coupled with the functionality and has a pattern differing from other traditional communication systems, e.g. MANET, where reliably and timely information delivery is the only target of the whole network. An example of the coupling between the communication and functionality in VANET is the wireless danger warning, where the value of information and the requirements of the communication performance vary from one vehicle to other depending on the position and status of the vehicle. Besides, in VANET the information is also processed during its propagation among vehicles. Communication patterns in VANET have to match its purpose too. A notable example of this is the GeoCast communication combining the broadcast and the vehicle position.
Therefore, instead of the highly abstracted metrics like throughput and delay, more interesting topic of VANET would be the information flow pattern for particular function (service), and for this information flow there must be a communication complexity region behind it.
Coming back to the topic of Cyber-physical-system, it's a interesting and promising area due to the evolution of wireless communications, sensor technology, embedded system, and network computing. There are definitely something interesting we can do ;-)
http://en.wikipedia.org/wiki/Cyber-physical_system
