IVR

Interactive voice response (IVR) is a technology that allows a computer to interact with humans through the use of voice and DTMF tones input via keypad. In telecommunications, IVR allows customers to interact with a company’s host system via a telephone keypad or by speech recognition, after which services can be inquired about through the IVR dialogue. IVR systems can respond with prerecorded or dynamically generated audio to further direct users on how to proceed. IVR systems deployed in the network are sized to handle large call volumes and also used for outbound calling, as IVR systems are more intelligent than many predictive dialer systems.

IVR systems can be used for mobile purchases, banking payments and services, retail orders, utilities, travel information and weather conditions. A common misconception refers to an automated attendant as an IVR. The terms are distinct and mean different things to traditional telecommunications professionals—the purpose of an IVR is to take input, process it, and return a result, whereas the job of an automated attendant is to route calls. The term voice response unit (VRU), is sometimes used as well.

Despite the increase in IVR technology during the 1970s, the technology was considered complex and expensive for automating tasks in call centers. Early voice response systems were DSP technology based and limited to small vocabularies. In the early 1980s, Leon Ferber's Perception Technology became the first mainstream market competitor, after hard drive technology (read/write random-access to digitized voice data) had reached a cost effective price point. At that time, a system could store digitized speech on disk, play the appropriate spoken message, and process the human's DTMF response.

As call centers began to migrate to multimedia in the late 1990s, companies started to invest in computer telephony integration (CTI) with IVR systems. IVR became vital for call centers deploying universal queuing and routing solutions and acted as an agent which collected customer data to enable intelligent routing decisions. With improvements in technology, systems could use speaker-independent voice recognition of a limited vocabulary instead of requiring the person to use DTMF signaling.

Starting in the 2000s, voice response became more common and cheaper to deploy. This was due to increased CPU power and the migration of speech applications from proprietary code to the VXML standard.

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