Final Report—February 2011
FHWA-JPO-11-052
Version 1.00

Appendix A—Description of the Current ITS Standards Program

Overview of Current Program

The USDOT's ITS Standards Program was started in 1991 as part of the department's implementation of the Intermodal Surface Transportation Equity Act (ISTEA) Section 6053(b) and was renewed in 1998 with the Transportation Equity Act for the 21st Century (TEA-21) and continues under current legislation (SAFETEA-LU). The mandates established for the ITS Standards Program in these two acts were:

• Develop and implement standards and protocols to promote widespread use of ITS technologies
• Promote compatibility among intelligent vehicle-highway systems technologies

In 2005 the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) Section 5307(a) expanded the above mandate by adding Standards Maintenance. From these mandates an overall goal was derived to develop standards that facilitate the deployment of interoperable transportation systems.

To achieve this overall goal, the ITS Standards Program uses a conventional four-stage life-cycle for each standard:

• Standards development
• Deployment support
• Testing
• Maintenance

Each standard that has gone through the above life cycle was proposed or selected as part of a standards planning process. The process included input from the National ITS Architecture and from proposals that came from industry participants through the standards development organizations (SDOs). Each of these life-cycle stages is described in the subsections below.

Originally, the USDOT's efforts were primarily focused on infrastructure-related standards. While other applications were addressed (e.g., vehicle-to-infrastructure or transit), overall the financial focus was on developing standards to support infrastructure applications.

Standards Development

USDOT established a partnership with selected SDOs to identify and develop ITS standards. The SDOs employed a consensus process involving agency representatives, vendors, vehicle manufacturers, integrators, consultants, and universities. At least four types of documents are included in the USDOT's ITS Standards Program:

• Information needed for a given interface.
• The protocol stack for an interface; covers a variety of protocols to address different architectures.
• Equipment, cabinets, application programming interfaces, and controller hardware.
• General category, used to define standards development approaches and act as guides for using ITS standards or reports on ITS standards-related projects.

ITS standards documents used to define interfaces have been or are undergoing development, and cover the following example types of interfaces (see Table 4):

Table 4: Types of interface examples

A first-generation set of ITS standards was developed using a design-centric approach. This approach defined message and object solutions but did not capture or specify needs, requirements, and dialogs. Early deployments revealed that the design-centric approach left gaps in addressing user needs and requirements and did not facilitate widespread deployment of interoperable systems. In 2001, a systems engineering process was proposed and later adopted for use on new and revised ITS standards to address these gaps in user needs and requirements.

USDOT has also been involved with developing International ITS standards primarily through the International Organization for Standardization (ISO). The results of this involvement include the development of Transportation Information and Control Systems—Requirements for an ITS/TICS Data Registry and ITS/TICS Data Dictionaries (ISO 14817) and Transportation Information and Control Systems—Data Interfaces Between Centres for Transport Information and Control Systems (ISO 14827 Parts 1 and 2). International ITS standards are developed in the ISO Technical Committee 204 (TC204), which incorporates 18 working groups related to ITS standards. The 2007 Transportation Review Board's (TRB) Study of Options for Streamlining Standards for ITS observed that the ITS Standards Program needed to foster an environment in which government agencies benefit from the competitive and innovative marketplace for ITS products and services. In the TRB panel's view, USDOT involvement in international standards forums is essential to achieve these goals.

Deployment Support

The purpose of deployment support is to promote wide-scale use of ITS standards in projects. Currently, the deployment program is focused on helping agencies deploy ITS standards. Deployment support activities are managed by FHWA's Office of Operations. Activities include:

• Developing processes and tools to help with procurement and testing activities for ITS standards dealing with interfaces.
• Developing guides to help deploy ITS standards on projects.
• Developing workshops to educate agencies and others in procuring interfaces for equipment and systems using ITS standards.
• Developing at least one workshop to educate agencies on the process of testing equipment and systems using ITS standards.
• Developing and delivering courses on ITS standards to help the transportation community understand the importance and benefits of using the ITS standards.
• Developing papers and pamphlets for outreach purposes.
• Developing case studies to capture lessons learned from projects implementing ITS standards.
• Providing Peer-to-Peer support.
• Providing deployment technical support for early adopters of ITS standards.

Testing

The purpose of testing ITS standards is to evaluate the standard's ability to facilitate the deployment of interoperable systems and to ensure that systems correctly incorporating ITS standards can be built economically and perform as desired.

The National Transportation Communications for ITS Protocol (NTCIP) Testing and Conformity Assessment (TCA) working group has developed guidelines for standards developers to help achieve the above goals for NTCIP standards. These include guidelines such as NTCIP 8007 (Testing and Conformity Assessment Documentation within NTCIP Standards Publications) and NTCIP 9012 (Testing and Conformity Assessment User Guidance to the Issues for Center-to-Field Communications and Field Devices).

Testing of ITS standards currently consists of two types. The first and more familiar type is to test standards that are design-centric. The second type is to test standards that are requirements-centric.

The first type of testing was conducted at sites that deployed one or more ITS standards to evaluate the “suitability, effectiveness, and contribution to interoperability and interchangeability of ITS standards.”¹ For each test, a set of core functions was identified, as part of the test, to help verify how conformant implementations were implemented. The end product, of this first type of testing, is a report identifying conformance to the standard(s), and identified issues that need to be addressed by later revisions of the standard(s).

USDOT conducted a second type of testing for some NTCIP standards that contain user needs and requirements. The purpose was to verify the completeness and correctness of the Dynamic Message Sign (DMS) standard, the DMS Procurement Guide, and the DMS Test Procedures. This testing also evaluated processes used by the agencies to procure and test during a project life cycle. Feedback was provided to the NTCIP DMS Working Group on how useful, complete, and correct the standard is from the users' perspective when used in an actual project.

Maintenance

The purpose of the maintenance stage is to support renewals at appropriate intervals and to update approved standards. In 2003, an agreement was established between USDOT and some of the SDOs for maintenance of their respective ITS standards. This agreement provides for free distribution of selected published standards over the Internet, and for upgrading these standards by the participating SDOs in exchange for USDOT-provided maintenance funding.

The funding of the SDO representatives for their time as managers of their standards programs; any travel associated with program management is accounted for in the maintenance funding life-cycle stage.

Status of Current Program

Each subsection below describes the current status of ITS standards of each life-cycle stage relative to the purpose for each stage.

Development Status

As of 2011, a total of 98 standards have been developed as part of the ITS Standards Program; of these, 65 are related to information and protocol interfaces and 10 are related to equipment and Application Programming Interface (API) specifications. The remaining documents are guides for the development of standards, white papers, reports on implementations or testing, and guides for the use of standards. Of the 75 standards used for deploying interfaces, equipment, and APIs, 23 are eligible for the SEP. An ITS Standard is eligible for the SEP if the standard deals directly with the operational or maintenance activities in a system and its operational user needs are not already addressed in another ITS Standard. For example, NTCIP 1202, Actuated Signal Controller (ASC), deals with the operational activities of a traffic signal system, is therefore eligible for the SEP. Of the 23 ITS standards eligible for the SEP, 10 have been or are currently going through the SEP.

The ITS-JPO involvement with the development of international ITS standards has evolved since program inception. The involvement has ranged from funding the position of Secretariat to ISO TC204, providing representatives on the Asia-Pacific Economic Cooperation (APEC) technical working group on ITS, monitoring activities, and providing US experts, to reducing the involvement to monitoring selected activities. The ITS-JPO is currently evaluating the level of commitment needed to support its objectives. In 2010, the ITS-JPO entered into an agreement with the European Commission and established the Standards Harmonization Working Group. ITS-JPO attended several international standards meetings in 2010, provided experts to international meetings, and jointly developed with the European Commission, a plan to harmonize standards around the vehicle platform.

Deployment Status

It is estimated that approximately 50 percent of the ITS interface standards have been deployed (if all or part of an ITS Standard was implemented in a project). However, the extent of the market penetration of ITS standards for projects that can use them is unclear. Of the NTCIP ITS standards deployed, the following are the most widely used:

• NTCIP 1202 Actuated Signal Controller (ASC)
• NTCIP 1203 Dynamic Message Signs (DMS)
• NTCIP 1204 Environmental Sensor Systems (ESS)
• ITE Traffic Management Data Dictionary (TMDD)

These deployments have identified the following key lessons that will help accelerate deployments, once resolved:

• Procurement processes have been developed to help achieve the goal of facilitating the deployment of interoperable systems, but these processes are generally unknown by the transportation community.
• ITS standards that have gone through the SEP contain user needs and requirements necessary for facilitating the deployment of interoperable systems.
• Consistent testing methods are needed to determine conformance.
• Inconsistent implementations still exist due to ambiguities in ITS standards.
• Incomplete standards (that do not satisfy all user needs) result in extensions that are implemented using proprietary solutions.

Once an ITS standard has been approved by the SDOs, feedback from deployments are provided to the SDOs for correction as part of the maintenance effort.

Testing Status

ITS-JPO has sponsored testing at six sites to evaluate a total of 14 ITS standards that were developed using a design-centric approach. The findings from these evaluations were provided as input to the associated ITS standards working groups.

The requirements-centric form of testing has so far only been conducted for the NTCIP Dynamic Message Sign (DMS) version 2 standard. Lessons learned from the procurement and testing activities have been extracted and have been submitted along with the test procedures, developed as part of the testing, to the NTCIP DMS Working Group.

Maintenance Status

Currently, 92 of the 98 first-version (v.1) ITS standards have been approved by the SDOs and are now in the maintenance stage. Of the total 98 ITS standards, 88 are available (i.e., online, hard copy, or both) from SDOs as first versions and, in some cases, updated versions. Three of the SDOs are providing the latest version of ITS standards available without charge to users under the terms of the maintenance partnership. This distribution agreement is renewable annually. Thirty of the approved ITS standards have completed or are in the process of completing revisions (amendments, version 2, or version 3).

It is anticipated that additional revisions will be needed as more ITS standards are deployed.

The maintenance effort includes addressing issues and corrections from feedback from ITS standards deployments.

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