"Functions" are a description of WHAT the system
has to do. In the National ITS Architecture, functions are defined
at several different levels, ranging from general subsystem descriptions
through somewhat more specific equipment package descriptions to Process
Specifications that include substantial detail. The equipment
packages that are associated with one or more elements in the Paris Regional ITS
Architecture are listed below. Each equipment package is a link to more
detailed information, including the portion of the Regional ITS
Architecture that implements the function, and the National ITS
Architecture Process Specifications that may be applicable.