This Fact Sheet was written on September 25, 2009. The status of the standard at the time was: Version 1.08 Published September 2005.
This Fact Sheet was written on September 25, 2009.
The status of the standard at the time was:
Published in September 2005.
This Fact Sheet was last verified on October 09, 2009
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 traffic control 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).
An application profile specifies a set of protocols and standards that define communications and interfaces at the highest levels. Within the context of the Open Systems Interconnect (OSI) Basic Reference Model, NTCIP application profiles are applicable to the three highest layers: the application, presentation and session layers.
This standard, NTCIP 2304 - Application Profile for DATEX-ASN (AP-DATEX), is one of the center-to-center protocols defined by the NTCIP. This standard specifies how DATEX-ASN is to be used within the United States. DATEX-ASN is also an international standard (ISO 14827 Parts 1 and 2) developed by the NTCIP Center-to-Center Working Group in cooperation with the International Organization for Standardization (ISO). The main DATEX-ASN specification permits various options; this standard ensures all implementations of DATEX-ASN within the United States use the same base options and therefore can be made to interoperate. If different traffic or transit management centers were to select different options, it could lead to a failure to interoperate, even though both use DATEX-ASN.
This standard, NTCIP 2304 - Application Profile for DATEX-ASN (AP-DATEX), is used by planners and deployers of center-to-center communications using DATEX-ASN. It is particularly useful for those responsible for preparing specifications or requirements for center-to-center communications. Those responsible for supplying DATEX-ASN based software in the United States may also refer to this document for base requirements.
Users refer to this standard, NTCIP 2304 - Application Profile for DATEX-ASN (AP-DATEX), to determine which DATEX-ASN options are appropriate for their applications. Of particular importance are the requirements for use of octet encoding rules (OER) for message encoding. The document also provides a- "profile requirements list,"- which is a checklist that can be used to choose between the various secondary options allowed by DATEX-ASN. The result is a Profile Implementation Conformance Specification (PICS). The format of this checklist enables the user to see the interdependencies between options so that compatible options can be chosen.
This standard, NTCIP 2304 - Application Profile for DATEX-ASN (AP-DATEX), is applicable to communications between any two management subsystems within the ITS environment. It lists the requirements for a traditional approach for data exchange among systems. This standard serves primarily as a pointer to detailed requirements in the ISO 14827 protocol standard. In addition to introductory material, it contains information on conformance and a profile requirements list.
The following ITS standards and documents are related and should be considered when using this standard:
The following standards and documents, while not part of the ITS standards, should also be considered when using this standard: