Low Level Function
1.3.1 Detect User

Overview

This Function shall be capable of providing the following facilities:

(1) The ability to detect the approach of a Traveller or Vehicle.
(2) When detected, the ability to trigger the other functionality in the Provide Electronic Payment Facilities Area.

Functional Requirements

(a) detect approaching vehicle or traveller,
(b) send a detection message to the identify user Function

Diagrams

The Diagram(s) is (are) the diagram(s) where you can find the function :
  • DFD 1.3 Perform Electronic Payment Transaction
  • Functional Tree of Area 1

    • Parent Higher Level Function

    Input logical dataflows

    Output logical dataflows

    User needs

    Number

    Description

    4.1.1.1
    The system shall have a minimum impact on the traffic flow, e.g. a short transaction duration.
    4.1.1.2
    The system shall have a minimum impact on the driving task.
    4.1.1.3
    The system shall not do anything to reduce the safety of either the travellers in the vehicle, or the staff close to the equipment, e.g. in toll booths.
    4.1.3.1
    The system shall be able to exchange financial information between roadside equipment (e.g. toll collection unit) and a moving traveller (e.g. a vehicle).