Standards Resources

The Institute of Transportation Engineers (ITE), on behalf of the Connected Intersections Project Committee, is pleased to announce the publication of the Connected Intersections (CI) Implementation Guide, known also as Connected Transportation Interoperability (CTI 4501 v01.00). This initial version of the CI Implementation Guide provides a detailed interface specification that can be used by the ITS community to deploy a nationally interoperable, openly available broadcast providing traffic Signal Phase and Timing and associated required mapping ("MAP") information that can be received by connected vehicles and other interested participants in the transportation system. This information enables applications such as Red Light Violation Warning and others that can increase both safety and efficiency. The Connected Intersections Project Committee accomplished this effort with broad stakeholder representation including standards development organizations , Intelligent Transportation Systems (ITS) infrastructure owner operators (IOOs), automotive original equipment manufacturers and suppliers, infrastructure equipment vendors, security specialists, ITS integrators, and end-users of data and services.

The Institute of Transportation Engineers, on behalf of the Roadside Unit (RSU) Standardization Working Group is pleased to announce the publication of RSU Standard Version 1.0, also known as Connected Transportation Interoperability (CTI 4001 v01.00). The RSU Standard is a non-proprietary, technology neutral, industry-based consensus standard for roadside units, based on stakeholder inputs and existing resources such as the RSU Specification Version 4.1, NEMA's TS-10 Connected Vehicle Infrastructure – Roadside Equipment Standard as well as lessons learned from pilot deployments. The RSU Working Group accomplished this effort with broad stakeholder representation including standards development organizations (SDOs), infrastructure owner operators (IOOs), automotive original equipment manufacturers (OEMs) and suppliers, infrastructure equipment vendors, security specialists, Intelligent Transportation Systems (ITS) integrators, and end-users of data and services

The Connected Transportation Interoperability (CTI) family of standards are a series of documents that are jointly developed by stakeholders across the connected vehicle spectrum, including infrastructure owner operators (IOOs), the automotive industries, device manufacturers, mobility data providers, and systems integrators. Sponsored by USDOT and approved and maintained by the following Standards Development Organizations (SDOs), including AASHTO, ITE, NEMA and SAE International. Documents in the CTI family includes standards and technical reports that provide guidance to develop and maintain an interoperable connected vehicle environment. This Roadside Unit (RSU) Standard v01 supersedes USDOT's Dedicated Short-Range Communications Roadside Unit Specifications v4.1. This RSU Standard v01 was developed by engaging with stakeholders representing the industry at large, including but not limited to infrastructure owner operators, automobile original equipment manufacturers (OEMs), RSU manufacturers, and the end users of data and services. This document establishes a non-proprietary, communications-agnostic, industry-based consensus RSU Standard

The Connected Transportation Interoperability (CTI) family of standards are a series of documents that are jointly developed by stakeholders across the connected vehicle spectrum, including infrastructure owner operators (IOOs), the automotive industries, device manufacturers, mobility data providers, and systems integrators. The documents in the CTI family are sponsored by USDOT and approved and maintained by the following Standards Development Organizations (SDOs), including AASHTO, ITE, NEMA and SAE International and includes standards and technical reports that provide guidance to develop and maintain an interoperable connected vehicle environment. This CI Implementation Guide address the ambiguities and gaps identified by early deployers and provides guidance to generate messages and develop applications for signalized intersections that are interoperable across the United States, especially for the automated transportation systems. This document focuses on harmonizing the existing signal phase and timing (SPaT) messages deployed, using the USDOT sponsored Cooperative Automated Transportation Clarifications for Consistent Implementations (CCIs) To Ensure National Interoperability Connected Signalized Intersections as a starting point.

Guide to V3.1 Traffic Management Data Dictionary (TMDD) Standard for Center to Center Communications

TMDD Standard v3.1 - Volume II Design Content

Notice of Intent to Adopt ATC 5401 Standard v02A - PDF

Notice of Intent to Adopt ATC 5401 Standard v02A - Word

Recommended Standard ATC 5401 v02A - PDF

Recommended Standard ATC 5401 v02A - Word

Standard Development Report for ATC 5401 v02A - PDF

Standard Development Report for ATC 5401 v02A - Word

Notice of Intent to Adopt ATC 5201 Standard v06A

Notice of Intent to Adopt NTCIP 1218 v01 Object. Definition for RoadSide Units (RSU)

ATC Joint Committee Web Conference Notes 06/20/19

Controller Working Group Comments on ATC 5201 v06.25

Recommended Standard ATC 5201 v06A - PDF