ITS Standards Fact Sheets
NTCIP 1202 - Object Definitions for Actuated Traffic Signal Controller Units
This Fact Sheet was written on September 18, 2009.
The status of the standard at the time was:
Published in November 2005.
This Fact Sheet was last verified on September 18, 2009
Check the ITS Standards Search to see if there has been subsequent development activity.
The National Transportation Communications for Intelligent Transportation System (ITS) Protocol (NTCIP) is a family of standards that provides both the rules for communicating (called protocols) and the vocabulary (called objects) necessary to allow electronic traffic control equipment from different manufacturers to operate with each other as a system. The NTCIP is the first set of standards for the transportation industry that allows transportation systems to be built using a "mix and match" approach with equipment from different manufacturers. Therefore, NTCIP standards reduce the need for reliance on specific equipment vendors and customized one-of-a-kind software. To assure both manufacturer and user community support, NTCIP is a joint product of the National Electronics Manufacturers Association (NEMA), the American Association of State Highway and Transportation Officials (AASHTO), and the Institute of Transportation Engineers (ITE). More information concerning the NTCIP family of standards and their related documents is available in the NTCIP 9001 - NTCIP Guide, available on-line at (www.ntcip.org).
Human communications relies on a vocabulary of words, each defined with a fixed meaning and spelling that are understood by the members of the conversation group. Computers have a similar vocabulary, called "objects" in the NTCIP standards. These objects define all possible commands, responses and information that may be exchanged among microprocessor-controlled electronic equipment, traffic management systems (which could include central computers housed in a center or portable computers, e.g. laptops), and by extension, their human operators. The NTCIP groups these objects by subject material (e.g., actuated signal controllers) and calls these groupings "object definitions." The objects defined in this standard allow an operator to command an actuated signal controller to do something and verify that the controller has accomplished the command.
What are these standards for?
This standard, NTCIP 1202:2005 - Object Definitions for Actuated Traffic Signal Controller Units, provides the vocabulary - commands, responses and information - necessary for traffic management and operations personnel to control, manage, and monitor Actuated Traffic Signal Controller Units. This standard contains object definitions to support the functionality of actuated traffic signal controller units used for transportation and traffic control applications. The standard includes conformance group requirements and conformance statements to support compliance with the standard.
Who uses them?
This standard, NTCIP 1202:2005 - Object Definitions for Actuated Traffic Signal Controller Units, should be used by transportation and traffic engineers involved with the design, specification, selection, procurement and installation, operation, and maintenance of actuated traffic signal controller units. ITS product hardware and software designers and application (computer program) developers should find this standard especially relevant to their efforts.
How are they used?
This standard, NTCIP 1202:2005 - Object Definitions for Actuated Traffic Signal Controller Units, defines a vocabulary of "objects" used to assure that the transportation management center computer-based devices, and actuated traffic signal controller units "speak" a common language. A message must be understood by the device it was intended for, and equally important, it must not be misunderstood or misinterpreted by another device on the same network. Object definitions unambiguously define the content, terminology, units and format of commands, responses and information affecting communications with actuated traffic signal controller units.
Users should determine which objects and groups of objects (listed in the standard as conformance groups) are needed to support the desired functionality for a given project in addition to the data ranges that should be supported.
This standard must be used with one of the NTCIP communications profiles (see related NTCIP documents below) which provide the communications channel for information transfer between devices. It must be used with the NTCIP Global Object Definitions (NTCIP 1201), which provides the glossary of common object definitions used by multiple NTCIP devices.
Communications between a transportation management center’s central computer and actuated traffic signal controller units are accomplished by using the objects defined in NTCIP 1202:2005 - Object Definitions for Actuated Traffic Signal Controller Units. These objects define the information, commands and responses that must be understood by the devices at both ends of the communications channel.
The following ITS standards and documents are related and should be considered when using this standard:
- NTCIP 1102 - Octet Encoding Rules (OER) Base Protocol
- NTCIP 1103 - Transportation Management Protocols (TMP)
- NTCIP 1201 - Global Object Definitions
- NTCIP 9001 - The NTCIP Guide
The following standards and documents, while not part of the ITS standards, should also be considered when using this standard:
- ISO/IEC 8824-1 -- Information technology - Abstract Syntax Notation One (ASN.1): Specification of basic notation
- ISO/IEC 8825-1 -- Information technology - ASN.1 encoding rules: Specification of Basic Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules (DER)
- IAB STD 15 - RFC 1157, A Simple Network Management Protocol
- IAB STD 16 - RFC 1155, Structure and Identification of Management Information for TCP/IP-based Internets
- IAB STD 16 - RFC 1212, Concise MIB Definitions
- NEMA TS 2 - Traffic Controller Assemblies with NTCIP Requirements
- IAB STD 17 - RFC 1213, Management Information Base for Network Management of TCIP/IP-based Internets: MIB-II
How to obtain Standards
- http://www.ntcip.org/library/documents/ Phone:
Jointly approved and published NTCIP standards are available for free download for 12 months through FHWA-sponsored special offer. More information is available at: http://www.ntcip.org/order/specialoffer.asp
- https://global.ihs.com/ Phone:
- http://ecommerce.ite.org/IMIS/iCommerce/Bookstore/Search_BookStore/iCommerce/Orders/SearchBookStore.aspx Phone:
202-289-0222 ext. 130