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Voice 101 #1: From Voice Messages to Voice Calls

With the demand for voice on the rise, it's important to get a grasp on all aspects of this technology available to your business.

May 16 2017

GSMA latest annual mobile engagement study found that 47% of mobile users are only using their mobile phones for talking and texting. The number is forecast to shrink to 29% by 2030 but still accounts for a large number of the population preferring voice and text. End user preference is something Infobip’s omnichannel solution is designed to address, giving you the ability to maximize customer engagement.

In today's modern world people not only listen to audio books, but also prefer interacting with digital assistants and smart home devices using voice commands and getting real time feedback on the go through voice. It is a trend that has been gaining speed in recent years.

What are Infobip Voice services

We’ve been developing our Voice services to help businesses reach and engage users around the world, providing an additional channel for communication with the end users and giving them the possibility to interact in their own preferred way.

Voice technology, like SMS, relies on the traditional Public Switched Telephone Networks (PSTN – the aggregate of the world’s circuit-switched telephone networks), which Infobip has a deep knowledge and understanding that is the result of years of developing and maintaining over 400 operator partnerships.

Infobip Voice services can be divided using the following general classifications:

  • Voice messages
  • Voice calls (SIP trunking):
    • Outbound
    • Inbound

 

Voice messages

Voice messages are similar to text messages except that the delivery to the end-user’s phone uses Voice technology instead of SMS technology and that they can be delivered to landline phones in addition to mobile phones, making this form of A2P communication convenient in cases where SMS would not be. It can be used as a standalone solution or it can be combined with other channels in order to push delivery rates as close as possible to 100%.

Modern enterprises need to be able to deliver information to a number of different types of destinations, depending on the end user’s capabilities for receiving communication. Voice messages are the ideal solution for this and can be used to solve a broad pallet of issues for enterprises.

When sending voice messages, what we are doing is either a text-to-speech conversion or using a previously recorded audio file to send an mp3 file that plays to the end user. Voice message, like any other message (SMS, OTT, email) has the possibility to be delayed for a period of time, retried, and sent in a specific time window.

For using text-to-speech, we currently support the following languages: English, Spanish, Catalan, Chinese (simplified and traditional), Danish, Dutch, French, German, Italian, Japanese, Korean, Norwegian, Polish, Portuguese, Portuguese – Brazilian, Russian, Swedish, Finnish, and Turkish.

Infobip: Voice message delivery flow

Other than only delivering Voice messages there is also the possibility of collecting responses made by the end-users to a message. In this case a channel is opened between our platform that made the call and the end user. This type of Voice call can be considered a session (similar to an USSD session) in which we can collect the Dual-tone multi-frequency inputs (DTMF tones – audible tones used by touch-tone telephones) from end users by recognizing the keypad numbers pressed on the phone.
 Infobip Voice - response code collecting flow
Using DTMF tones, voice messages can be used to ask the end user to perform an action. This interaction is called Interactive Voice response (IVR) and is performed by the end user pressing keypad numbers on his or her device.
Voice messages can also be used to perform 2FA (2-Factor Authentication), and deliver one time PIN codes to users.
 

Live outbound conversations Voice calls (SIP trunking)

Voice calls are a live form of P2P communication that allow our clients to call a destination and have a live conversation with the person on the other side.
This is done through a SIP trunk (Session Initiation Protocol), a connection made between our client’s software that can initiate SIP requests and our IP core. This results in lower costs of Voice traffic while also giving the ability to reach all of the destinations in the World that are in our Voice calls coverage.

Infobip: Outbound Voice call flow

Receive live inbound Voice calls (SIP trunking)

The benefits for inbound Voice calls are similar to the previously mentioned outbound Voice calls. By using this method to receive incoming calls to a single location you can remove the geographical boundaries that you would have if using traditional lines and also cut costs significantly.

Infobip offers a large list of Voice capable DID (Direct Inward Dial) numbers which can be used to redirect or forward calls to:

  • Another voice-enabled number (existing mobile or landline number)
  • IP address (interconnect IP PBX, Softswitch or SIP phones available on a static IP address)

The image below shows how inbound Voice traffic is being forwarded to an IP address where an IP PBX, SBC or Softswitch is set up.

Infobip Voice - Call Forwarding to IP flow It is also possible to do a call to a transferred number. In this case a call comes to a DID number, operators forward the traffic to our platform which then calls the number where the call is being transferred to and the caller that initiated the call is then connected to that number.

Infobip Voice - Call Forwarding to PSTN flow

Infobip’s IP/PSTN forwarding is always implemented according to local and international regulation and best practices governing this type of service.

Find out more about how our Voice service can help you

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