Phone switchboards are used for routing telephone calls and adding advanced features to telephone systems. Traditional electromechanical devices have been largely replaced by computer-based applications that reside on web servers, application servers, or personal computers (PCs). Features such as call routing and text-to-speech (TTS) recognition are commonly available.
Today, there are two basic types of phone switchboards: interactive voice response (IVR) and automatic call distribution (ADC). IVR switchboards are used in smaller-scale applications where callers need to speak to specific person, such as the manager of a customer service department. IVR phone switchboards connect callers with a remote database and allow two-way communication. The caller can use voice commands and/or press specific keys on the telephone keypad. ADC switchboards are also computerized, but are designed for larger-scale applications such as call centers.
There are two types of interactive voice response (IVR) phone switchboards: inbound and outbound. Inbound IVR switchboards allow businesses to route calls, manage queues, record greetings, capture leads, and provide information. Outbound IVR is used to provide event invitations, appointment reminders, inventory alerts, shipment updates, and customer satisfaction surveys. Complete inbound and outbound IVR phone switchboards are also available. Traditionally, IVR switchboards were platform-dependent and used proprietary protocols.
To simplify the deployment of voice-based applications, the Worldwide Web Consortium (W3C) standardized VoiceXML, a tag-based language that is based on extensible markup language (XML). VoiceXML provides a high-level programming interface for speech and telephony applications and is supported by major telecommunications hardware suppliers. Businesses that use VoiceXML can continue to use proprietary backend and middleware systems. Automatic call distribution (ADC) systems are phone switchboards that distribute incoming calls sequentially, to the first available operator. They are used to reduce wait times in call centers at large-scale businesses such as credit card companies. ADC phone switchboards can use either caller ID or automatic number identification (ANI) to capture the caller’s telephone number. Typically, they use a form of computer-supported telecommunications architecture (CSTA), an abstraction layer that is independent of underlying protocols. Computer telephony integration (CTI) is often used to establish external routing, allowing call center agents to view data on their computer screens while answering customer phone calls.