Why a System Architecture?
The Intelligent Vehicle Highway System (IVHS) is a large umbrella program that consists of a number of different user services in the categories of travel and traffic management, public transportation management, electronic payment, commercial vehicle operations, emergency management, and advanced vehicle safety systems. These services are related in that they all involve collecting, transmitting, processing, distributing, and displaying information. Moreover, the same information may be common to different user services and system components may be designed to accommodate requirements for multiple services. The complexity and enormity of IVHS, its numerous and byzantine interconnections, and its far-reaching applications and implications all demand that it be put together from the start in a well-thought-out manner. This up-front planning will ensure that the deployment of IVHS user services will occur within the most sensible system framework. It will also ensure that a nationally co