This document specifies data elements and data frames for messages

a) exchanged between roadside modules and:

1) signal controllers,

2) traffic management centres, and/or

3) other roadside modules.

b) exchanged between traffic management centres and signal controllers.

NOTE Roadside modules can generate data based on inputs from vehicle detectors and/or probe data transmitted by vehicles. This document does not address how the roadside module generates the data; it only addresses communication after receiving and processing raw data from one or more sources.

EXAMPLE A roadside module can calculate vehicle volume, average speed, and queue length by utilizing data from vehicle detectors and probe information.

The data structure follows the framework specified in ISO 14817-1, and the data elements and data frames are described by description name, object identifier, definition, and data type following ISO 14817-1. The specifications of this document complement those from ISO/TS 19091 and other standards.

The roadside modules can be constructed in any manner using any architecture including the ITS station as described in ISO 21217, or other hardware and software constructs.