In telecommunication, the term facility has the following meanings:

1. A fixed, mobile, or transportable structure, including (a) all installed electrical and electronic wiring, cabling, and equipment and (b) all supporting structures, such as utility, ground network, and electrical supporting structures.

2. A network-provided service to users or the network operating administration.

3. A transmission pathway and associated equipment.

4. In a protocol applicable to a data unit, such as a block or frame, an additional item of information or a constraint encoded within the protocol to provide the required control.

5. A real property entity consisting of one or more of the following: a building, a structure, a utility system, pavement, and underlying land.

Source: from Federal Standard 1037C and from MIL-STD-188 and from the Department of Defense Dictionary of Military and Associated Terms