The Telephony Application Programming Interface (TAPI) is a Microsoft Windows API, which provides computer telephony integration and enables PCs running Microsoft Windows to use telephone services. Different versions of TAPI are available on different versions of Windows. Information from Wikipedia
The purpose of the TAPI specification is to provide control of telephony resources to applications. This is used primarily to control either Modems or, more recently, to control business telephone system (PBX) handsets. When controlling a PBX handset, the driver is provided by the manufacturer of the telephone system. Some manufacturers provide drivers that allow the control of multiple handsets. This is traditionally called “third-party control”. Other manufacturers provide drivers that allow the control of a single handset. This is called “first-party control”. Third-party drivers are designed to allow applications to see and/or control multiple extensions at the same time. Some telephone systems only permit one third-party connection at a time. First-party drivers are designed to allow applications to monitor and/or control one extension at a time. Telephone systems naturally permit many of these connections simultaneously. Modem connections are by nature first-party.
Tapi can also be used to control voice-enabled telephony devices, including voice modems and dedicated hardware such as Dialogic cards.
TAPI compliant hardware
Telephony hardware that supports TAPI includes most voice modems and some telephony cards such as Dialogic boards.
The following telephone systems provide Tapi drivers. Many of these drivers are licensed and thus incur a charge to use:
Aastra (WOW Edition)
Alcatel OXO
Alcatel OXE
AltiGen
Artisoft Televantage
Avaya Index
Avaya IP Office
Cisco Call Manager
Cisco Call Manager Express (First-party)
Cisco Communication Manager
Elmeg
InterTel Axxess (First-party)
LG LDK
Mitel 3300 (discontinued)
NEC-Philips iS3000
NEC Aspire
NEC XN120 (Topaz)
Nortel BCM
Nortel CS
Nortel Meridian
Nortel Norstar
Panasonic KX-TD
Panasonic KX-TDA
Panasonic KX-TDE
Panasonic NCP
Samsung OfficeServ
Siemens 3000 (First-party)
Siemens HighPath 4000
Siemens HighPath 8000
Siemens TC35i
Shoretel
Tadiran
Toshiba CT (First-party)
Vertical Televantage
IP Telephony with TAPI 3.0
Updated April 1999
Summary: Telephony Application Program Interface (TAPI) 3.0 is an evolutionary API providing convergence of both traditional PSTN telephony and IP telephony. IP telephony is an emerging set of technologies that enables voice, data, and video collaboration over existing LANs, WANs, and the Internet. TAPI 3.0 enables IP telephony on Microsoft® Windows® operating systems by providing simple and generic methods for making connections between two or more computers and accessing any media streams involved in the connection.
TAPI 3.0 supports standards-based H.323 conferencing and IP multicast conferencing. It uses the Microsoft Windows 2000 operating system’s Active Directory™ service to simplify deployment within an organization and includes quality-of-service (QoS) support to improve conference quality and network manageability. (33 printed pages)
Contents
IP Telephony
Introduction to TAPI 3.0
H.323 Communications in TAPI 3.0
IP Multicast Conferencing in TAPI 3.0
Quality of Service
Enterprise Deployment of TAPI 3.0 IP Telephony Infrastructure
TAPI 3.0 and NetMeeting 2.0
IP Telephony
IP telephony is an emerging set of technologies that enables voice, data, and video collaboration over existing IP-based LANs, WANs, and the Internet.
Specifically, IP telephony uses open IETF and ITU standards to move multimedia traffic over any network that uses IP, offering users both flexibility in physical media (for example, POTS lines, ADSL, ISDN, leased lines, coaxial cable, satellite, and twisted pair) and flexibility of physical location. As a result, the same ubiquitous networks that carry Web, e-mail, and data traffic can be used to connect to individuals, businesses, schools, and governments worldwide.
TAPI 3.0 is an evolutionary API that supports convergence of both traditional PSTN telephony and telephony over IP networks.
Benefits of IP Telephony
IP telephony allows organizations and individuals to lower the costs of existing services, such as voice and broadcast video, while broadening their means of communication to include modern video conferencing, application sharing, and whiteboarding tools.
In the past, organizations have deployed separate networks to handle traditional voice, data, and video traffic. Each with different transport requirements, these networks were expensive to install, maintain, and reconfigure. Furthermore, since these networks were physically distinct, integration was difficult, if not impossible, limiting their potential usefulness.
IP telephony blends voice, video, and data by specifying a common transport, IP, for each, effectively collapsing three networks into one. The result is increased manageability, lower support costs, a new breed of collaboration tools, and increased productivity.
Possible applications for IP telephony include telecommuting, real-time document collaboration, distance learning, employee training, video conferencing, video mail, and video on demand. See Figure 1.
TAPI Explained (source-Microsoft)
