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Oct 2, 1995

GENEVA, Telecom 95, October 2, 1995 -- National Semiconductor Corporation is now shipping the first and only Telephony Application Programming Interface (TAPI) Service Provider software for Local Area Network connected PCs. The software is integrated with the company's isoEthernet(tm) ISA Adapter cards that are now shipping to end users through its OEM partners.

The software enables high performance real-time interactive multimedia applications and provides a platform for all current and future TAPI enabled applications for Windows 3.1, Windows for Workgroups, and Windows 95 systems. Establishing "phone call connections" for real-time voice, video, data conferencing and telephony processing applications from the LAN connected PC is now a reality.

This unique call control or "signaling" software runs entirely on the PCs' processor and interfaces to the TAPI service provider interface. This allows existing TAPI applications such as Telephony Dialers, Automatic Call Centers, Video Conferencing and Teleconferencing to interface to networking hardware such as isoEthernet (IEEE 802.9a) and other isochronous communications protocols such as ISDN and ATM. A first release which supports National's isoEthernet Network Interface Card provides the basis for a number of system demonstrations focusing on computer telephony integration (CTI) and real-time interactive multimedia at Telecom 95 (Geneva) and NetWorld + Interop (Atlanta).

"Our objective is to enhance the PC as a business tool which entails providing the user a means of personal communications in many forms," said J. Michael Sodergren, Strategic Marketing Director of National's Interactive Multimedia Group, "The networked personal computer and the phone systems have become mission critical desktop assets. On demand, real-time interactive voice, video, and data communications will play an increasingly critical role, so we are implementing network solutions, such as isoEthernet, which can deliver this capability to the desktop environment. The Microsoft Windows environment and isoEthernet transport offer a user friendly platform for true integration and synchronization of high Quality of Service (QoS) computer telephony. By leveraging standard communications capabilities in Microsoft Windows, like TAPI, we can exploit a broad base of applications with a new networking technology".

"Communication, whether from the home or the office, is becoming central to the Windows PC." said Charles Fitzgerald, Product Manager, Microsoft Personal Systems Division. "TAPI provides an architecture that virtualizes the telephone network, just as printer or display drivers are virtualized in Windows today, so the same applications can run against existing telephone networks or new network technologies. By using TAPI, National Semiconductor leverages the work of a wide variety of applications developers to bring telephony applications onto the LAN infrastructure."

National's software is modular, increasing the flexibility of the solution to address different hardware subsystems and operating environments. A Call Control module implements real-time signaling and bandwidth management for the ISDN, ATM and isoEthernet environments, while a Call Driver and Data Link Manager provides the link to a standard LAP-D implementation which provides a guaranteed, reliable and sequenced delivery of call control messages. An operating system independent, hardware abstraction layer provides a means of concluding the link to the network signaling channel provided by the media (e.g. 64kbps, D-channel). In addition, the release allows control of local switch fabric via a Switch Manager which assigns specific time slots to multiple streams or channels based upon the application needs.

This simplifies the interface and control of subsystems incorporating video CODECs (H.261,MPEG), HDLC packet drives and ATM SARs. "National's TAPI service provider software, together with TAPI applications, allow for enterprise desktops and remote locations to take advantage of connection oriented LANs and ISDN technologies," said Scott Pickett, applications director of National's Interactive Multimedia Group. "By leveraging the PC platform's resources, National's solution offers a cost effective, distributed and scalable method for deploying computer telephony and multimedia communication applications."

Extensive interoperability testing has been implemented with a variety of products. Multiple TAPI applications have stressed compliance of the service provider software. The TAPI based call control has been verified against Windows NT(tm), UNIX, 0S2(tm), and Macintosh(reg) based call control, call server, and hub products.

For more information about isoEthernet, please contact National's Customer Response Group at 49-0180-532-7832 in Europe.