Alcance
                            This document defines an application interface between DSRC-based OBE (hereinafter referred to as "DSRC-OBE") and an external in-vehicle device (hereinafter referred to as "the external device") to make DSRC-OBE applicable for diversified external devices.NOTE    For use in autonomous tolling and DSRC-based (CEN, UNI, ARIB, TTA and GB/T) electronic fee collection (EFC) systems. For use in urban and inter-urban toll schemes.The scope of this document covers the following items (as shown in Figure 4):—     definitions of the application interface between DSRC-OBE and external devices, including global navigation satellite system (GNSS), cellular network (CN) and controller area network (CAN) device;—     definitions of data groups and data elements.Figure 4 — Scope of this documentThe following items are out of the scope of this document:—     definitions of hardware components in the external device such as GNSS module, CN module and mobile devices;—     definitions of the physical interface between DSRC-OBE and the external device such as USB and Bluetooth;—     definition of ITS services other than EFC;—     definition of algorithms for authentication, encryption and key management.