H-GAC TSMO - ITS Standards

ITS Standards Why Use ITS Standards? Brief Introduction to ITS Standards Regional ITS Standards Standards Project Example

ITS Standards

Standards Development Organizations (SDOs) have taken the lead in developing and publishing ITS standards. Some standards documents are very restrictive, including mandatory requirements, while others more general and include recommended or optional specifications. Agencies deploying ITS in the Houston region should realize that different SDOs use varying terminology for their standards products. The brief coverage of ITS standards in this report is intended to give some indication of the different terminology and applications of standards developed by the various SDOs. This information may help those who use (or specify the use) of ITS standards when developing systems and procuring ITS equipment.

Why Use ITS Standards

ITS standards define the data elements used within ITS systems so that elements can interconnect and exchange information. ITS standards are not “design” standards and do not specify specific products, they define the ways in which data flows to and from various ITS elements. ITS standards address various "communications layers" in their description of how data is transmitted between systems.

The layers start with descriptors of how bits of data are combined and transmitted in singular messages over a communications path. ITS standards attempt to specify compatibility of data interconnects and interfaces, both hardware and software.

The common advantages of using ITS standards are:

Facilitating compatibility and interoperability of components from different manufacturers.
Reducing cost since agency managers can purchase the most cost effective components from different vendors that will work together.
Expanding a standards compliant existing system that is easier and less expensive.
Flexibility in vendor selection.

Some of the disadvantages of using standards that have been noted include:

For first time implementation of standards, time and effort required to understand and specify standards requirements for procurement.
Component testing required to ensure they are standards-compliant.
Need staff or consultant who is knowledgeable with use of standards.
Data packets for certain standards protocols may be larger requiring longer transmission times.Flexibility in vendor selection.

Brief Introduction to ITS Standards

The USDOT has an ITS standards program that supports multiple SDOs in development and testing of ITS standards. The program also encourages transportation agencies to deploy standards based ITS systems. SDOs involved with development of ITS Standards are listed below.

American Association of State Highway and Transportation Officials (AASHTO)
American National Standards Institute (ANSI) Accredited Standards Committee (ASC) X12
American Society for Testing and Materials (ASTM)
Institute of Electrical and Electronics Engineers (IEEE)
Institute of Transportation Engineers (ITE)
National Electrical Manufacturers Association (NEMA)
Society of Automotive Engineers (SAE)

Lists of all the standards that have been published and approved, are waiting approval, and are under development can be found at ITS Standards Program website (http://www.standards.its.dot.gov/). The website also provides valuable deployment resources in the form of technical assistance, training, and publications related to best practices and lessons learned.

USDOT offers technical assistance with standards development and use. Some of the resources include:

The ITS Standards Implementation Program

http://ops.fhwa.dot.gov/int_its_deployment/standards_imp/standards.htm
Offers ITS standards implementation resources, technical assistance, training, and guidance through the ITS Standards Implementation Program.

FHWA ITS Standards Program Field Support Team

o http://www.ops.fhwa.dot.gov/int_its_deployment/standards_imp/stdsteam.htm
Provides short-term, on-call, technical assistance from FHWA staff and experts from the private sector.
ITS Standards Search (http://www.standards.its.dot.gov/stdssearch.asp)
FHWA and FTA ITS Specialists, through regional offices.

ITS Peer-to-Peer Program - Provides short-term technical assistance to:

State and local Departments of Transportation
Transit agencies
Metropolitan and Statewide Planning organizations
Emergency and public safety organization
Motor carrier offices

ITS Help Line

Toll-free Help Line at 866-367-7487 between 8:00 AM to 5:00 PM Eastern Time, M-F
Via email: [email protected]

Regional ITS Standards

Many of the ITS systems in use in the region are legacy and pre-date the development of national ITS standards. While that is acceptable per federal law, eventually those systems will have to be significantly upgraded or replaced and it is the policy of this region to adopt the national ITS standards where opportunities exist to do so. It is suggested that the following procedure be used to determine what standards may apply to a particular ITS project:

Determine the classes used in the ITS project
- a) Center to Center
- b) Center to Field
- c) Center to Vehicle/Traveler
- d) Field to Field
- e) Field to Vehicle
Identify the standards area, which apply to your project:
- a) Center to Center
  - i) Data Archival
  - ii) Incident Management
  - iii) Rail Coordination
  - iv) Traffic Management
  - v) Transit Management
  - vi) Traveler Information
- b) Center to Field
  - i) Data Collection/Monitoring
  - ii) Dynamic Message Signs
  - iii) Environmental Monitoring
  - iv) Lighting Management
  - v) Ramp Metering
  - vi) Traffic Signals
  - vii) Vehicle Sensors
  - viii) Video Surveillance
- c) Center to Vehicle/Traveler
  - i) Mayday
  - ii) Transit Vehicle Communications
  - iii) Traveler Information
- d) Field to Field
  - i) Highway Rail Intersection
- e) Field to Vehicle
  - i) Probe Surveillance
  - ii) Signal Priority
  - iii) Toll/Fee Collection

Once a project has been classified (and one project can have multiple classifications), refer to the USDOT standards support website (which will be linked via the HGAC RITSA webpages) for applicable standards. Those standards are not listed within this document as their status may change or they may be updated occasionally.

Much of the compliance to these standards may be satisfied by vendor certifying that their equipment meets certain groups of standards, so individual agencies will not likely need to thoroughly test equipment for compliance, but include language for vendor compliance in procurement specifications.

As a region, the intent is to rely on the National ITS Standards effort in order to leverage the USDOT investments in standards development. As part of ITS project review, agencies should be prepared to submit details on which ITS standards will be used, and how transition from legacy systems will be achieved.

Standards Project Example

As an example, a project that deals with Center to Field (C2F) Traffic Signals, depending on the specifics of the project, could currently have the following applicable 21 national standards applied to the project:

NTCIP 1102: Octet Encoding Rules (OER) Base Protocol
NTCIP 1103: Transportation Management Protocols (TMP)
NTCIP 1201: Global Object Definitions
NTCIP 1202: Object Definitions for Actuated Traffic Signal Controller (ASC) Units
NTCIP 1209: Data Element Definitions for Transportation Sensor Systems (TSS)
NTCIP 1210: Field Management Stations (FMS) - Part 1: Object Definitions for Signal System Masters (Under Development)
NTCIP 1211: Object Definitions for Signal Control and Prioritization (SCP)
NTCIP 2101: Point to Multi-Point Protocol Using RS-232 Subnetwork Profile
NTCIP 2102: Point to Multi-Point Protocol Using FSK Modem Subnetwork Profile
NTCIP 2103: Point-to-Point Protocol Over RS-232 Subnetwork Profile
NTCIP 2104: Ethernet Subnetwork Profile
NTCIP 2201: Transportation Transport Profile
NTCIP 2202: Internet (TCP/IP and UDP/IP) Transport Profile
NTCIP 2301: Simple Transportation Management Framework (STMF) Application Profile
NTCIP 2302: Trivial File Transfer Protocol (TFTP) Application Profile
NTCIP 2303: File Transfer Protocol (FTP) Application Profile
NTCIP 8003: Profile Framework
NTCIP 9001: NTCIP Guide
ITE ATC Controller 5.2: Advanced Transportation Controller (ATC)
ITE ITS Cabinet: ITS Standard Specification for Roadside Cabinets
SAE J2266: Location Referencing Message Specification (LRMS)