TAPI version 2.1 implements TAPI Client Management, which provides full client-server telephony and enhanced server administration tools.
TAPI 2.1 works with Microsoft Windows NT Server version 4.0 and supports applications on Windows NT Workstation version 4.0 and Windows 95 operating systems. TAPI 2.1 provides a most powerful and flexible platform for developing and using computer-telephony integration (CTI) applications and provides complete client support for Windows 95.