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Real-Time System Management Information Program Data Exchange Format Specification

Executive Summary

Real-Time System Management Information Program (RTSMIP)

Section 1201 of the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU), published in August 2005, instructed the Secretary of Transportation to “…establish a real-time system management information program (RTSMIP) to provide, in all states, the capability to monitor, in real-time, the traffic and travel conditions of the major highways of the United States and to share that information to improve the security of the surface transportation system, to address congestion problems, to support improved response to weather events and surface transportation incidents, and facilitate national and regional highway traveler information.” Additional information about Section 1201 is available. (Real-Time System Management Information Program – FHWA Operations.)

In response to these requirements, U.S. Code of Federal Regulations (CFR) 23 Part 511 was developed. Title 23 CFR Part 511 requires each state to establish and operate a Real-Time System Management Information Program (RTSMIP) as part of its Intelligent Transportation System (ITS) capable of gathering and making available the data for traffic and travel conditions. However, Title 23 CFR 511 does not require the dissemination of real-time information in any particular manner, only that the states make the information available. It also does not require states to apply any particular technology, technology-dependent application, or business model for collecting, processing and disseminating information. As a result, development of a Data Exchange Format Specification (DXFS) and implementation guidance was initiated to support the need of states for a specification that satisfies the essential elements of the rule.

Data Exchange Format Specification (DXFS)

In 2011, U.S. DOT began development of the Data Exchange Format Specification (DXFS) to facilitate the development of interoperable real-time traffic and travel information between public agencies, with other public agencies, and with private entities.

A primary objective of the DXFS is to establish a standards-based specification of key RTSMIP interfaces. To align with the objective the scope of the DXFS is the set of interfaces used to send traffic, transit, transportation-related weather, and traveler information from one agency to another. The provision of this data directly to travelers is not part of the scope of the specification. While the DXFS covers all the information defined in Rule 23 CFR 511, the scope of the DXFS has been expanded beyond the information defined in the rule to include transit information and additional traffic information that is relevant to the exchange of data between agencies (and other parties). The DXFS is a specification that can be used to define the information exchanges across a system-to-system interface, thus providing interoperability of systems that implement the DXFS. The DXFS does not specify communication protocols, but it does refer to existing standardized protocols that can be used for transferring the data.

Users of the DXFS

The DXFS has been developed to assist the following groups of users to specify and then develop an RTSMIP implementation:

  • Transportation Agencies. This group includes state DOTs and regional transportation related organizations (e.g., a municipal DOT or Public Works or a transit agency) that are developing systems that implement aspects of the RTSMIP.
  • Public Safety Agencies. This group includes state, county, or local public safety agencies that develop systems that support RTSMIP.
  • Traveler Information Organizations (Public or Private). This group includes providers of traveler information whether public or private that are involved in the development of systems that support RTSMIP.
  • Development Contractors. This group includes contractors who have been hired by transportation or public safety agencies to develop procurement packages that would specify aspects of RTSMIP, or contractors who have been selected to perform the development of RTSMIP related projects.