Office of Operations
21st Century Operations Using 21st Century Technologies

Model Systems Engineering Documents for Dynamic Message Sign (DMS) Systems


Beacon An external device that directs light in one direction and flashes. The device is intended to increase a driver's attention to a message.
BOS Blank Out Sign - A type of DMS that has the capability to show a blank message or one fixed message.
Central Computer A computer system that operates as a control source for one or more signs in the signage system. A computer/server that is host to its signs, also referred to as the host or central computer. The signage system may be controlled by central computers installed in more than one location. Or, it may be a remotely located central computer capable of managing the operation of one or more signs.
CFR Code of Federal Regulations
CMS Changeable Message Sign - A sign that is capable of displaying one of two or more predefined messages, or a blank message.
COTS Commercially available Off-The-Shelf. This is an FAR term defining a non-developmental item of supply that is both commercial and sold in substantial quantities in the commercial marketplace, and that can be procured or utilized under government contract in precisely the same form as available to the general public.
DMS Dynamic Message Sign - Any sign system that can change the message presented to the viewer such as VMS, CMS and BOS. It includes the following major components: sign face, sign housing, controller, and, if present, the controller cabinet.
DMS Controller A device used to control and monitor the operations of a sign. It can have a variety of control interfaces, such as a local control panel, a local field programming terminal, or a central computer.
DMS Management System See Central Computer.
Dynamic Message Sign (DMS) System The overall system that manages DMS to convey information to the traveling public. The software communicates with the DMS in the field from a central location such as a TMC/TOC.
External Device A component that is not normally considered part of a DMS, but is connected to the DMS by some interface.
FAR Federal Acquisition Regulation
Field Programming Terminal A portable computer running maintenance software. It can communicate with a sign controller, control activation of the sign, and perform diagnostics on the controller.
ITS Intelligent Transportation System
Low-bid Contract awarded to the "lowest responsible bidder". Bid is based on a complete set of plans and specifications that precisely defines the facilities to be built.
NEMA National Electrical Manufacturers Association
NTCIP National Transportation Communications for Intelligent Transportation System Protocol
PIF Public Interest Finding
Real-time Activity that occurs simultaneously with or very soon after an event. For example, real-time control involves taking action based on measurements immediately after the measurement is completed.
RFI Request For Information
RFP Request For Proposal
RFQ Request For Qualifications
Specification The project-specific detailed requirements for a DMS to be purchased by an agency or a statement by a manufacturer defining the detailed features provided by the DMS.
TMC Transportation or Traffic Management Center - The location of the DMS Management System central computer and equipment which allows operations staff to monitor and manage traffic through roadside field devices (e.g. vehicle detectors, VMS, etc.).
TOC Transportation or Traffic Operations Center – See TMC

Office of Operations