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Office of the Assistant Secretary for Research and Technology
ITS Joint Program Office

Application Areas

Traffic Signals


This center-to-field application area covers the interface between a traffic management center and a specific type of roadway equipment that provides signalized intersection control-a local traffic signal controller. Also included in this application area is the interface between the center and an on-street master controller (a field master) that manages a group of local signal controllers. Based upon an analysis of traffic characteristics for a given time and type of day, the traffic management center invokes the appropriate pre-configured traffic signal control system timing plan, including simple pre-timed (fixed) and complex actuated control schemes, which is sent to the field masters and/or traffic signal controllers at the roadside. Traffic sensors that detect traffic flow are also controlled by the traffic management center and are included in this application area.
This graphic shows the scope of the Center to Field Traffic Signals application area.  This scope is described in the preceding text.
National ITS Architecture Interface
This application area includes the interface between the Traffic Management Subsystem (TMS) and the traffic signal control equipment and traffic sensors in the Roadway Subsystem (RS). The TMS monitors and manages the traffic signal controllers in the RS, which also includes the field masters, and other ancillary equipment associated with the traffic signal control system, such as traffic sensors. Signal controllers are typically pre-configured locally for safety reasons. Once the initial configuration of the local traffic control is accomplished, a TMS can remotely control traffic signal operation by selecting and invoking a preloaded timing plan, downloading new timing plans, and adjusting other control parameters. The TMS can request operational status of the field devices, including queries on equipment condition. The traffic signal controller and traffic sensor equipment respond with the current operating status information, event logs, alarms and volume reports.

Applicable Standards

In general, the following standards are applicable to Traffic Signals deployments. To determine which specific standards are applicable for a deployment you will need to determine which architecture flows will be needed for the Traffic Signals piece of your deployment. Contact your local FHWA ITS Division Specialist or an ITS Standards Program Field Support Team contact

Standard Development Status
ATC 5201 (ITE ATC Controller) Advanced Transportation Controller (ATC) ; Published
ATC 5301 Advanced Transportation Controller (ATC) Cabinet Version 02; Published
ITE ATC API Application Programming Interface (API) Standard for the Advanced Transportation Controller (ATC); Published
NTCIP 1102 Octet Encoding Rules (OER) Base Protocol; Published
NTCIP 1103 Transportation Management Protocols (TMP); Published
NTCIP 1201 Global Object Definitions; Published
NTCIP 1202 Object Definitions for Actuated Traffic Signal Controller (ASC) Units; Published
NTCIP 1209 Data Element Definitions for Transportation Sensor Systems (TSS); Published
NTCIP 1210 Field Management Stations (FMS) - Part 1: Object Definitions for Signal System Masters; Published
NTCIP 1211 Object Definitions for Signal Control and Prioritization (SCP); Under Development
NTCIP 2101 Point to Multi-Point Protocol Using RS-232 Subnetwork Profile; Published
NTCIP 2102 Point to Multi-Point Protocol Using FSK Modem Subnetwork Profile; Published
NTCIP 2103 Point-to-Point Protocol Over RS-232 Subnetwork Profile; Published
NTCIP 2104 Ethernet Subnetwork Profile; Published
NTCIP 2201 Transportation Transport Profile; Published
NTCIP 2202 Internet (TCP/IP and UDP/IP) Transport Profile; Published
NTCIP 2301 Simple Transportation Management Framework (STMF) Application Profile; Published
NTCIP 2302 Trivial File Transfer Protocol (TFTP) Application Profile; Published
NTCIP 2303 File Transfer Protocol (FTP) Application Profile; Published
NTCIP 8003 Profile Framework; Published
NTCIP 9001 NTCIP Guide; Published
SAE J2266 Location Referencing Message Specification (LRMS); Published
Deployment Resources
Deployment resources can be found in the deployment resources section.