AIOD leads are Terminal equipment

Terminal equipment

In telecommunication, the term terminal equipment has the following meanings:* Communications equipment at either end of a communications link, used to permit the stations involved to accomplish the mission for which the link was established....

 leads used solely to transmit automatic identified outward dialing (AIOD) data

Data

The term data refers to qualitative or quantitative attributes of a variable or set of variables. Data are typically the results of measurements and can be the basis of graphs, images, or observations of a set of variables. Data are often viewed as the lowest level of abstraction from which...

 from a PBX to the public switched telephone network

Public switched telephone network

The public switched telephone network is the network of the world's public circuit-switched telephone networks. It consists of telephone lines, fiber optic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables, all inter-connected by...

 or to switched service networks (e.g., EPSCS), so that a vendor can provide a detailed monthly bill identifying long distance calling usage by individual PBX stations, tie trunks

Tie line

A tie line, also known as a tie trunk, is a communication connection between extensions of a private telephone system, typically two PBXes.-References:...

, or the attendant

Attendant

Attendant may refer to:* Car attendant, a railroad employee* Flight attendant, flight crew employed to ensure the safety and comfort of the passengers* Museum attendant* Toilet attendant, maintains standards in a toilet and collects any usage fees...

. It resembles common channel signalling in that the AIOD leads provide data for all trunks, but is used only for billing, thus resembling automatic number identification

Automatic number identification

Automatic number identification is a feature of telephony intelligent network services that permits subscribers to display or capture the billing telephone number of a calling party. In the United States it is part of Inward Wide Area Telephone Service . ANI service was created by AT&T for...

.