Advanced telephony-computing applications and services the new powerful dimension of ISDN PBXs

Abstract

Time is a crucial factor in business and every possibility is investigated to speed up the daily work in oflces. For instance, dialing a phone number is a purely mechanical task, and there is no reason why this function should not be performed more eflciently by a computer program. The advent of ISDN PBXs establishes a new form of close cooperation between a PBX and a computer system. This allows advanced telephony-computing applications and services to control both switching and processing functions. The modern ISDN PBX Hicom (registered trademark) from Siemens fulfilLF the high market requirements for linking telephone handling andcomputer processing by offering capabilities for line integration, device integration anct/or fully functional application integration This superior level of integration is achieved by ISDN D-channel protocols and CSTA interfnces (Computer Supported Telephony Applications) being stanabrdized. Hicom enables computer programs to access and control a rich variety of its sewices andfunctions. The CSTA-like interconnection via Hicom 's Applications Connectivity Linksupports the implementation of any type of integrated voice-dota package, from simple software telephones to automatic call distribution, hotel applications, etc. Its use has been agreed upon with several leading computer vendors. This article shows the requirements for today's voice-data integration in ofices. describes the different approaches t o w a d thisgoal, outlinesthe Hicom fentunsandinterfaces for computer cooperation with emphask on the Applications Connectivity Link and gives examples of typical telephony -computing applications. (ISDN = IntegratedSewices Digital Network; PBX = Private Branch Exchange) 1. MARKET' REQUIREMENTS FOR PBX AND COMPUTER W I N G Today's Situation: Separate Devices for Telephoning and Computing Today's ofices arc still characterized by a variety of standalone deviees and systems often not interworking well with each other. Use of the telephone in most cases is not an integral part of the computer applications implemented to support office work (refer to Figure 1). Therefore, users of office systems often still have to operate the telephones individually by hand for the repeated business proceduns. Goal: Integrated Telephoning and Computing Users should be able to accomplish typical office functions with just OM uscr interface on just one terminal, even if the telephone equipment is a separate device on the desk. All neccssaw teleDhone actions should be S U D W I ~ C ~ asmuch as wssible client's name and other information to the clerk's terminal display to support further actions in response to what the client is ordering. This relieves the clerk from routine, time consuming and error prone tasks such as looking up telephone numbers, dialing the numbers, switching to handsfree talking, hanging up etc. Computer supported telephony lets the user complete tasks that are part of everyday office work together and in one step. Example: an incoming call is redirected by an application to a message desk. When the operator answers the phone call, the application supplies an electronic absence message of the originally called party at the operator's terminal. He can inform the caller accordingly, take electronic notes and mail them to a specified mailbox, switch the caller to a substitute partner or a voice-mail box etc. By the time the operator hangs up, all operator actions are completed. The benefits of computer supported telephony are obvious: it is cost-effective for businesses by improving usage of resources and increasing productivity of personnel; it makes placing phone calls considerably easier, safer and faster and makes connecting a caller to the right department and to the right person more convenient. Possible Solutions for PBX and Computer Cooperation Effcient solutions for tasks like the message desk just described require. the functional integration of voice and data handling at a person's desk. This integration can best be provided by computer applications with access to services of a private telephone switching system (PBX). The computer application can control both the operation of the data terminal and the operation of the telephone on a desk. The PBX on the other side has to provide new types of services, which gives the "I" (integrated) and "S" (services) in the abbreviation ISDN a new practical meaning. In a typical telephony-computing scenario (Figure 1) a desk usually has a data terminal and a telephone. The terminal is always controlled by a computer application and the telephone is controlled by a PBX. The terminal normally is connected by a public data network ' computer network computing functions I telephony functions I