entity that is external to the system but with which the system communicates either to obtain inputs or to which it can send outputs

NOTE 1 Terminators may be split up into actors if necessary.

NOTE 2 In most ITS architectures, the terminators may be the same in both the functional and the physical viewpoints.

NOTE 3 In the US National ITS Architecture, a terminator defines the boundary of the system of interest. Each terminator may represent the people, systems and general environment that interface to ITS. The interfaces between terminators and the sub-systems and processes within the National ITS Architecture are defined, but no functional requirements are allocated to terminators. The logical and physical architecture views of the National ITS Architecture both have exactly the same set of terminators.