This data flow represents information for trains or hi-rail vehicles approaching a specific highway grade crossing and their crews. It is provided by HRI traffic control elements to rail owned and operated wayside interface equipment (train signaling circuits, automatic control interfaces, local connections to centralized sites via railroad communications networks, etc.). This is a time critical flow and requires the most direct communications path available to a train approaching a grade crossing. This data flow consists of the following data items each of which is defined in its own DDE:

+ twe-stop_highway_indication
+ twe-hri_status

Sub Data Flows

Parent Data Flows

Associated PSpecs