Glossary > Additional Terms

Additional Terms

Below is a list of additional terms:

The clear identification of the architecture products that will be maintained, including specific format and version information. Changes to the architecture baseline must follow approved change management processes typically documented in a Maintenance Plan. The architecture baseline will change over time as the architecture is revised.

Document that describes the strategy that will be used to prevent deterioration of Congestion Management System performance.

TEA-21 requires that each Transportation Management Area develop a congestion management system that provides for effective management of new and existing transportation facilities through the use of travel demand reduction and operational management strategies.

Also known as "Major Investment Studies," these are used to flesh out transportation strategy and project recommendations on a geographical basis. A corridor or sub-area is a context for evaluating how specific transportation conditions, problems, and needs should be addressed within the defined geographic area. A wide range of multimodal strategies, including ITS, are considered as candidate solutions for these problems.

Description of the inputs (stimuli) to the system, the outputs (responses) of the system, and behavior relationships between the inputs and outputs. The level of detail contained in a Functional Requirements Specification is dependent on the stakeholders (especially the system implementers) understanding and familiarity with the particular ITS implementation. At a Regional ITS Architecture level, the Functional Requirements Specification should contain high-level requirements that focus on project functionality and the interface definition between projects.

Established as a federal mechanism for financing the accelerated highway program, the highway trust fund is a source of funds from which ISTEA and later TEA-21 authorizes expenditures.

Institutional integration represents the process of combing existing and emerging institutional constraints and arrangements. Integration is at least two-fold in a region; technical integration involves the functional act of integration while institutional integration addresses the agency and/or regional environment for integration. Both are necessary components for interoperable systems.

Legislative initiative by the United States Congress that restructured highway funding for transportation programs. ISTEA authorized increased levels of highway and transportation funding and in increased role for regional planning commissions/MPOs in funding decisions. The Act also requires comprehensive regional and statewide long term transportation plans and places an increased emphasis on public participation and transportation alternatives.

A guide for long term implementation of ITS in the state, metropolitan area, or region. A strategic plan will normally include identifying regional transportation needs and then defining ITS elements to be implemented over time, aimed at meeting those needs. An ITS strategic plan is most effective when considered as an integral part of the metropolitan or statewide transportation planning process.

Description of configuration control and update guidelines for Regional ITS Architectures and/or Project ITS Architectures. The primary purpose of the maintenance plan is to maintain an Architecture Baseline.

Institutional agreement that contains a description of the level of effort and integration details necessary for sharing information between ITS elements. An MOU can also address sharing of equipment, maintenance, enforcement, operations, control, etc. An MOU can be used to create a more detailed agreement such as an interagency, intergovernmental, operational, funding or master agreement.

This document is the official metropolitan, intermodal transportation plan that is developed through the regional transportation process.

Intelligent infrastructure distributed along the transportation network which perform surveillance, information provision, and plan execution control functions and whose operation is governed by center subsystems. Roadside subsystems also directly interface to vehicle subsystems. One of the four general subsystem classes defined in the National ITS Architecture.

See Subsystem Diagram.

The line that surrounds a specific service or agency that provides a service. An example is the service borders of a transit agency. The transit agency provides services that do not go beyond a defined boundary.

This is a set of 14 Standards Requirements Packages that presents detailed data and interface requirements for the priority standards that need to be developed to implement the architecture. It is primarily intended for Standards Development Organizations and system designers.

A document required to be prepared periodically by each state that contains one or more "air-quality non-attainment" areas that describes specific projects that will be constructed and/or operated over the next several years (minimum three years, some areas include additional years). ISTEA/TEA-21 and the Clean Air Act require that these states demonstrate in the SIP that planned transportation programs will not exacerbate the existing air-quality problem.

This is a document prepared by each state that is a staged, multi-year, statewide, intermodal program of transportation projects which is consistent with the Statewide Transportation Plan and planning processes and Metropolitan Transportation Plans, TIPs and processes.

The Traceability Document is a technical document that is used in conjunction with and throughout the development of the logical architecture and physical architecture. It lists all the user service requirements, which constitute the highest-level functional specifications for ITS, as provided by the U.S. Department of Transportation. In several tables, these USRs are mapped to the various logical and physical components of an ITS system. The document should be used primarily by those involved in detailed design.

This document is prepared by the transit agency and identifies transit needs and the changes in services and systems that are recommended to better meet those needs. It will feed information to both the Transportation Plan and the Transportation Improvement Program.

Passed in 1997 by the United States Congress to address the need to begin work toward regional integration of transportation systems. TEA-21 is the successor reauthorization of the ISTEA legislation.

This is a document prepared by each Metropolitan Planning Organization listing projects to be funded with FHWA/FTA funds for the next one to three year period. It is consistent with the Metropolitan Transportation Plan.

All urbanized areas over 200,000 in population and all other areas that request designation.

A communications link serving stationary sources. It may be implemented using a variety of public or private communications networks that may physically include wireless (e.g., microwave) as well as wireline infrastructure. Both dedicated and shared communications resources may be used. One of the four types of architecture interconnects defined in the National ITS Architecture.

For more information regarding this project, contact Mitchell Prevost at mitchell.prevost@dot.ca.gov

For more information regarding this project's web site, contact Melissa Hewitt at Melissa.Hewitt@kimley-horn.com