This International Standard provides the specifications of: — common AVI/AEI transaction requirements, which define the common steps of any AVI/AEI transaction; — AVI/AEI application interface to standardized wireless protocols (referred to as the “Air Interface”) supporting the AVI transaction requirements, so as to enable interoperability. In Figure 1 the conceptual architecture model is shown for AVI transactions between “On-board Equipment” and “Fixed Equipment”. The air interface concerns the reference point DELTA in ISO 14814. This is an interface standard, adhering to the open systems interconnection (OSI) philosophy (ISO/IEC 7498-1), and it is as such not concerned with the implementation choices to be realized at either side of the air interface between the “Fixed Equipment” and “OBE”.