One of the key elements of the DCMS is the DCtrac. The DCtrac enables the advanced distributed architecture of the DCMS. Each element controlled by the DCMS (CCR, selector switch, ATS, generator, beacon, etc.) has a DCtrac. The unit is a microprocessor-based module that includes all communication, command, monitoring, input/output and fail-safe functions. The DCtrac operates the controllable elements according to the air traffic controllers' commands

and transfers the status of these elements back to the controllers and to the operations and maintenance. The DCtrac is installed on or near the controllable elements and is connected to the DCMS redundant communication network via quick connectors. The distributed structure generated by the DCtrac and the DCMS redundant communication networks simplifies installation and significantly increases reliability and ease of maintenance. All the DCtrac use identical interchangeable hardware, which is also used for the various types of controllable elements.
The DCtrac differ in the address and several other parameters, which are field-programmable. The procedure for adapting a DCtrac for use in a specific controllable element or for replacing a damaged DCtrac, includes address setting and parameter loading. The address and parameters are set in a simple dialogue between the operator	DCtrac Module
and the computer, and do not require any specific knowledge or background beyond familiarity with the use of computers. Download of the controllable element parameters can be done locally from a notebook PC connected to the DCtrac, or remotely.