TAPI versions 2.0 and earlier did not contain TAPI Client Management, and a user had access only to TAPI devices (telephone lines, modems, phones, and so on) that were physically attached to the computer. There was no easy way to let a user have access to only a single line in a private branch exchange (PBX) system.
TAPI Client Management enables TAPI (versions 2.0 and later) to be a viable platform for a PBX through the following telephony client/server support and administration features: