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Voice Bot

Voicegain as a single ASR for both Speech IVRs & Voice Bots

This post highlights how Voicegain's deep learning based ASR supports both speech-enabled IVRs and conversational Voice Bots.

This can help Enterprise IT organizations simplify their transition from directed dialog telephony IVR to a modern conversational Voice Bot.

This is because of a very important feature of Voicegain. Voicegain's ASR can be accessed in two ways

1) MRCP ASR for Speech IVR - the traditional way: Voicegain ASR can be invoked over MRCP from a VoiceXML IVR application developed using Speech grammars. Voicegain is a "drop-in" replacement for the ASR used in most of these IVRs.

2) Speech-to-Text/ASR for Bots -  the modern way: Voicegain offers APIs integrate with (a) SIP telephony or CPaaS platforms and (b) Bot Frameworks that present a REST endpoint. Examples of bot frameworks supported include Google Dialogflow, RASA and Azure Bot Service.

Directed Dialog IVRs are not going away any time soon!

When it comes to voice self service, enterprises understand that they would need to maintain and operate traditional Speech IVRs for many years.

This is because existing users have been trained over the years and have become proficient with these speech enabled IVRs. They would prefer not having to learn  new user interface like Voice Bots if they can avoid it. Also enterprises have made substantial investments in developing these IVRs and they would like to continue to support these IVRs as long as they generate adequate usage.

However an increasing "digital-native" segment of customers demand Alexa-like conversational experiences as it provides a much better user experience compared to IVRs. This is driving substantial interest by enterprises to develop Voice Bots as a long term replacement for IVRs.

Net-net, even as enterprises develop new conversational Voice Bots for the long term; in the near term, they would need to support and operate these IVRs .

Bots & IVRs use different ASRs, protocols and App tech stacks

ASR: While both Voice bots & IVRs require ASR/Speech-to-Text, the ASRs that support conversational voice bots are different from the ASRs used in directed dialog IVRs. The ASRs that support IVRs are based on HMMs (Hidden Markov models) and and the apps use speech grammars when invoking the ASR. On the other hand, voice bots work with large vocabulary deep learning based STT models.

Protocol: The communication protocols between the ASR & the app are also very different. An IVR App, usually written in VoiceXML, communicates with the ASR over MRCP; modern Bot Frameworks communicate with ASRs over modern web-based protocols like WebSockets and gRPC.

App Stack: The app logic of a directed dialog IVRs is built on VoiceXML compliant application IDE. Popular vendors in this space Avaya Aura Experience Portal (AAEP), Cisco Voice Portal (CVP) and Genesys Voice Portal or Genesys Engage. This article explores this in more detail.

On the other hand, modern Voice bots require Bot frameworks like Google Dialogflow,, RASA, AWS Lex and others. They use modern NLU technology to can extract intent from transcribed text. Bot Frameworks also offer sophisticated dialog management to dynamically determine conversation turns. They also allow integration with other enterprise systems like CRM and Billing.

When it comes to Voice Bots, most enterprises want to "voice-enable" the chatbot interaction logic which is also developed on the same Bot Framework and then integrate with telephony. - so use a phone number to  "dial" the chatbot and interact using Speech-to-Text and Text-to-Speech.

The Solution: Use Voicegain ASR to support both IVRs & Bots

The Voicegain platform is the first and currently the only ASR/ Speech-to-Text platform in the market that can support both a directed dialog Speech IVR and a Conversational voice bot using a single acoustic and language model.

Cloud Speech-to-Text APIs from Google, Amazon and Microsoft support large vocabulary speech recognition and can support voice bots. However they cannot be a "drop-in" replacement for the MRCP ASR functionality in directed dialog IVR.

And  traditional MRCP ASRs that supported directed dialog IVRs (e.g. Nuance,  Lumenvox etc) do not support large vocabulary transcription.

Integration with Bot Frameworks and Telephony

Voicegain offers Telephony Bot APIs to support Bots developers with providing the "mouth" and the "ear" of the Bot.

These APIs are Callback style APIs that an enterprise can can use along with a Bot Framework of its choice.

In addition to the actual ASR, Voicegain also embeds a telephony/PSTN interface. There are 3 possibilities:

1. Integration with modern CPaaS platforms like Twilio, SignalWire and Telnyx  With such an integration, callers can now have  "dial and talk" to their chatbots over a phone number.

2. SIP INVITE from CCaaS or CPaaS Platform: The Bot Developer can transfer the call control to Voicegain using a SIP INVITE. After the call has been transferred, the Bot Framework can interact using above mentioned APIs. At the end of the bot interaction, you can end the Bot session and continue the live conversation on the CCaaS/CPaaS platform.

3. Voicegain embedded CPaaS:  Voicegain has also embedded the Amazon Chime CPaaS; so developers can actually purchase a phone number and start building their voice bot in a matter of minutes.

Essentially, by using Telephony Bot APIs alongside any Bot Framework, an Enteprise can have a Bot framework and an ASR that serves all 3 self service mediums - Chatbots, Voicebots and Directed Dialog IVRs.

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