Railroad operators use the 455 transaction set to register and communicate parameter trace configurations for monitoring and tracking shipments throughout the rail network. Typically sent by a railroad carrier or logistics provider to a receiving railroad or operations center, this transaction set establishes or updates the specific parameters that will govern real-time trace monitoring of freight movements. The mandatory BTC (Beginning Segment for Parameter Trace Registration) segment initiates the registration request and provides core identification information, while the LX (Assigned Number) segment introduces repeating loops that organize individual trace parameters, and the PRM (Basic Trace Parameters) segment specifies the actual monitoring criteria such as measurement intervals, alert thresholds, or data collection points.

Union Pacific Railroad sends a 455 transaction to CSX Transportation’s operations center to register trace parameters for a high-value automotive parts shipment moving from Chicago to Atlanta. Within the message, Union Pacific specifies via the ED (Equipment Description) segment the rail car identification numbers involved, establishes monitoring checkpoints at key junctions through multiple LX loops each containing F9 (Origin Station) and D9 (Destination Station) segments, and defines in the PRM segments whether temperature, location, or door-open events should trigger alerts. CSX receives this registration, activates the trace configuration in their monitoring system, and uses the geographic and temporal parameters to ensure comprehensive visibility throughout the shipment’s journey.