Let’s say you want to develop a service where a SmartHome monitoring system detects smoke and a phone call is generated to alert the homeowner. With the ability to receive external events from any monitoring software, there’s a free, open source communications software for creating voice and messaging products for that.
FreeSWITCH is a softswitch for PBX applications which can create that phone call alert and then connect the homeowner to the 911 operator. In this situation, it allows you to generate calls for automation systems where you play audio files, collect user input, and then decide to make another call and have two parties talk to each other. In this case, with FreeSWITCH you can also receive external events from external programs, such as the home monitoring system, and can generate calls remotely. Its built-in Interactive Voice Response (IVR) system lets you play a pre-recorded audio file, collect user input (usually dtmf digits) and make decisions — either to play something else or to generate another call, hang up or basically anything else within the phone system. Some of this functionality is provided by external systems that are integrated using FreeSWITCH modules.
There’s more to FreeSWITCH than this one use case. You can use FreeSWITCH to develop text-to-speech engines where you can turn any text into an audio file and then play it, or have your audio files professionally pre-recorded and then play it while still receiving user input. Or the reverse, use it for speech recognition such as when you want cell phone voicemail messages to also appear in a text format. It’s very suitable for voicemail and eFax applications. FreeSWITCH works with Linux and Windows, and supports English, French, German and Russian languages.
FreeSWITCH is quite popular with telecommunications software developers who need to create automated telemarketing programs. Using FreeSWITCH as a base, you can generate automated telemarketing calls where FreeSwitch generates the call, plays a pre-recorded audio file and then hangs up.
It can be used to develop services which receive incoming calls to the FreeSWITCH for one leg of the call, play an audio file and based on what the user wants to do, connect to another application, such as voicemail. Or create a service where when the user receives a voicemail, they can also receive an email with an attached audio file telling them that a voicemail is waiting for them.
Our Northforge team has created voice and messaging services based on FreeSWITCH for several customers who want to expand or start new services. Based on our experience with this open source software, we can get our customers telecom programs up and running quickly.