Anything that says “Open Source” is thought to be freely available, customizable and really exciting for many software users. (Specially people from India who are very price competitive, but I am sure Open source software sounds tempting to people all over the world!) Open Source alternative for any popular application software has almost become a industry practice and specialised Software, IVR too followed the same with some CTI vendors providing open source IVR platform for developers.

Thus Asterisk has almost become synonymous with Open Source IVR as well as Telephony Systems. Many companies have developed numerous Telephony solutions based on Asterisk.

While Open Source has many backers and takers, a newbie may still be confused when to choose Open Source
IVR or Telephony Application! First let us look at what one saves by using Open Source Telephony platform :-

A typical IVR System consists of the following components:-
1. Application Software ( IVR Call Flow)
2. Operating System/ Database
3. CTI Cards
4. PC or Server

By using Open Source Telephony platform, one saves #1 and #2 above! But is it a significant saving for you in the long term ?

1. According to me, one should choose Open Source if a company has spare manpower who is proficient in Linux and good in Linux based programming Languages. Many start up companies where the founders are normally engineers with programming background may choose Open Source IVR as they would be able to maintain the IVR without any extra cost! But for a company which may have to dedicate one or two manpower to develop and maintain the IVR systems, it may not be beneficial at all, in the long run!

2. Another advantage of choosing Open Source IVR is, the CTI cards seem to be less costlier than the CTI cards which have APIs. It is majorly because of the fact that, these CTI boards use host PC’s computing resources and does not have on-board DSPs to perform all those telephony signalling, audio processing. So if one is really constrained by budget, one may choose Open Source Telephony platform.

Some people are die hard fans of Linux and Open Source. For them, it is natural to choose Open Source IVR. But they should consider few things below :-

Other than Traditional Open Source ( Linux OS + Asterisk or FreePBX), there are IVR toolkits too available which provide the Toolkit free of cost and charges just per channel licenses at deployment! For example, VBVoice IVR Toolkit is freely downloadable along with 2 channel free license!

Apart from this kind of “offline” Tool kit, now a days, almost every company provides IVR in Cloud! Here anyone can design an IVR in a visual tool online and use as per usage!

Hope this may help how and when to choose an open source IVR!

Microsoft Corporation, the veteran company, leader ( almost monopoly) in PC operating system has bought Skype, the voice call provider on internet ( peer to peer Skype account as well as any telephone to Skype account and vice versa ).

Microsoft Acquires Skype : New Voice Apps

If it does so, than we may experience many interesting changes the way we have been creating call flow of IVR, IVVR etc.

CTI manufacturers have been making CTI boards supporting Asterisk, the open source Telephony Software so far, but now, they may start manufacturing CTI boards in future directly supporting MSXML for building rich voice and video application eying the 170million Skype users ( growing at 40% Year over Year).

So, we hope the acquisition of Skype by Microsoft seems exciting for IVR World!

I6NET Solutions and Technologies, an R&D company based in Madrid, Spain has recently released their latest version of popular VXML Browser VXI* VoixwXML Browser. This browser works on Asterisk on Linux Operating System. Asterisk is open source Telephony software development tool, now widely used to develop IVR and Voice Applications.

VXI* is native integration between the Asterisk Open Source Telephony engine and VoiceXML, one of the most advanced voice and video application’s standard language. VXI* is an advanced complementary software for Asterisk-based IVR systems. Adding VXI* to any Asterisk server enables access to the large VoiceXML applications world. You will get great advantages in opening your favourite PBX to the new evolution of IVVR (Interactive Voice & Video Response) and web enabled applications. More details, one may visit here.

The release post of this version of VXI* Browser says :-

There’s very important improvements and new specific ASR features in this new release, that will provide you the best IVR experience for your voice and video telephony projects. VXI* 5.2 is suitable for production platforms running with all lastest Asterisk 1.4, 1.6 and now 1.8 kernels! (all Asterisk’s packages are available for download too).

Few of the enhanced features are :-

# mod: Correction in the fonction wait/silence (wait for openvxi).
# add: Add the parameter dialnumbersonly to filter called numbers.
# mod: Change the open sequence for better reactivity.
# mod: Increase the number of accounts to 200.
# add: File descriptors counters (with show top).
# add: Average statistiques (duration, response and CAPS).
# mod: Replace the nanohttp library by the libcurl.
# add: Extra parameters in the transfer (after mark ‘,’) for to the Dial command.
# add: Command line parameters -U and -G to change the OpenVXI linux user/group.
# mod: Correction for uniMRCP to stop the speech/ASR engine.
# mod: Correction for disable bargein with the speech/ASR.
# add: Increase the Asterisk compatibility (disable the using the channel context).
# mod: Ignore the ASR result if a DTMF interaction occured.
# add: Support the attribut repeat for SRGS/XML DTMF grammars.
# add: Options to pass all the SRGS/XML grammars to the ASR engine (voice and DTMF).
# add: Support for Asterisk 1.8.

For complete details : Visit I6Net Website.

Recently, I have started getting mails about asking open source IVR as well as its availability for free, download-able from internet! Most of the people who have asked me about “‘Open Source IVR” have heard about Asterisk. Before going into the details about Asterisk, being open source IVR, I would like to clarify few things about IVR ( Interactive Voice Response)  System.

IVR system consists of  four components, one can say. They are :-

1. CTI ( Computer Telephony) board
2. Call Flow development as per requirement
3. Voice prompts, TTS ( Text To Speech) Engine  and ASR (Automatic Speech Recognition) Engine
4. Host PC or Server for #1 through #3 above.

1. CTI ( Computer Telephony) board

CTI board is a hardware and I m quite sure, nobody will make it ‘open source’ or free for anyone! The other alternative is SIP ( Session Initiated Protocol) on VoIP ( Voice Over Internet Protocol). But for connecting to PSTN ( Public Switched Network), TDM based CTI Board is a must and there is no alternative, as of now!

All CTI boards come with their own set of API ( Application Programming Interfaces) to control telecom protocols and call handling. Dialogic, the biggest CTI company provides many APIs as well as sample codes in three major operating systems, Windows, Linux and MAC OS. Likewise, other CTI vendors too provide their proprietary C++ API for at least two OS.

2. Call Flow development as per requirement

There are many online as well as offline call flow development tools. Some Call Flow development tools are completely pictorial visual tool where one can drag and drop various call flow like components to make a call flow. Some others use simple ‘English’ like/natural language like scripts to define call flow. Incidentally, all these tools are free to use for developing the call flow, but to execute these call flow, one has to pay per port licenses.

VXML is standard call flow development language adopted by W3 which uses HTML like simple syntax. Presently this requires a third party interpreter which again requires per port licenses.

3. Voice prompts, TTS ( Text To Speech) Engine and ASR (Automatic Speech Recognition) Engine

Voice prompts are normally recorded in a studio by professional artists. One can also record voice prompts using computer/laptop and MIC for development purpose. There are many open source, freely available TTS. Even MS SAPI is freely available. eSpeak, a popular TTS which has support for many languages from all around the world, is an open source TTS which works well both in Windows and Linux.
Likewise there are many open source ASR that works well after refinements.

Now, major challenge is to integrate all these components and build a reliable IVR system. Now a days, IVR is no longer simple call flow of yes and no by the caller, but complex system with data retrieving from multiple sources. It performs complex task as well compute input data by caller, make a decision and respond to caller with appropriate answer.

Most of the time, making an informed choice of IVR which is most suitable for a particular IVR application is quite difficult.

Now finally, Asterisk is a truly open source telephony system with IVR facility. It is Linux based and supports many CTI hardware and many developers contributing to it. It is a completely DIY ( Do It Yourself) IVR platform. It may not be easy to develop an IVR system quickly for a beginner using Asterisk from a scratch. At the end, it may be as difficult as building IVR using native API available with CTI board itself.

Many high density and widely deployed CTI hardware are not supported by Asterisk. This is one disadvantage which Asterisk will take some time to overcome. And at the end, while some one tries to customise Asterisk, he might end up with his own proprietary piece of codes, specific to some CTI hardware only!

Advantage of using API of CTI board is the freedom of choice of operating system as well as programming language. Programming languages like C++ offer power of ‘real programming’ language to complete complex tasks as well as integrate with any third party software.

So, one may not have much choice as Open Source IVR!

There has been lot of talk about video IVR or IVVR ( Interactive Voice and Video response System) recently. Dialogic also has announced recently of their availability of Beta DiaStar™ Server, Version 1.1, “Allowing developers to create video applications for fixed and mobile phones. this brings into variety of existing video features into open source marketplace.” (Dialogic Press release) Indeed a good news for large open source Asterisk IVR/IVVR developers.

Dialogic Releases Beta DiaStar

Dialogic is no doubt the leader in the field of CTI boards, Telephony Signaling products in the world and this initiative by Dialogic to make their existing Video enabled products accessible by open source developer community will boost the development of video IVR applications.

Now, can Video IVR or IVVR can be the next big VAS for Telecom operators ?

I think so and here are my reasons:-

1. 3G is available
3G has been introduced almost everywhere in the world including big Telecom market India by state run mobile service providers BSNL ( Bharat Sanchar Nigam Limited) and MTNL ( Mahanagar Telecom Nigam Limited). MTNL operates in two big Indian metros New Delhi and Mumbai while BSNL operates all circles in India other than New Delhi and Mumbai. 3G is the requirement for video call in the mobile network and 3G enabled phone is the requirement at the user end. 3G enabled mobile phone with twin camera for video calls have been in the market for long time now. Also entry level 3G enabled with camera is now available at less than $100, even in India. So using video applications or services by large number of users is a reality in India.

2. Innovative Video Application
Think about getting an SMS alert about Mahendra Singh Dhoni’s huge six with a link to make video call to watch it! Or an SMS alert informing about Irphan Pathan getting out Ricky Ponting out by a yorker ? Who in India or in Indian subcontinent want to miss it ? Video IVR creates possibility of many innovative video application which will entice user to avail video value added services! If YouTube could be such a hit, video IVR with large contents and innovation would also be hit!

3. Concept of citizen journalism or citizen activism
People are getting used to the idea citizen journalism now. With video IVR, there will be people who would be uploading video footage about events immediately for large audience which will be available simultaneously on internet, TV or mobiles of any 3G users!

4. Customer care
Video IVR may revolutionize customer care and call center industry! With video call, many problems by customers could be solved remotely as proper instruction could be provided to the customer for self-help. Frustration with traditional voice based IVR where they are made to speak to machine, by customers would also reduce as through video IVR, they can discuss with customer care executives face to face!

5. Video Advertising, blogging, cinema etc.
Video blogging can be expected to increase by many fold! Video portal would have much larger audience with 3G users. People would be able to watch trailer on movies before they buy a ticket for it over video IVR! SMS advertising would give away to video advertising now! Watch TV advertising on your mobile!

6. Utility Services
A user will be able to video weather conditions live at any place! Phone banking will be replaced by video banking which will make it more secure as well as personal! It will be very useful in healthcare industry where specialist would be able to instruct many locations simultaneously from a remote location!

So, innovation and ideas are many for video IVR applications! So, if video IVR is introduced after 3G, it may be the next big VAS ( Value added service) for mobile operators!

What is Asterisk ?

Asterisk is the world’s leading open source telephony engine and tool kit. Offering flexibility unheard of in the world of proprietary communications, Asterisk empowers developers and integrators to create advanced communication solutions…for free.
Asterisk® is released as open source under the GNU General Public License (GPL), and it is available for download free of charge. Asterisk® is the most popular open source software available, with the Asterisk Community being the top influencer in VoIP. Source : www.asterisk.org

In other words, you can create IVR application using Asterisk as a platform! Do they support Dialogic cards ? They support some Dialogic card but they are mainly supporter of Digium cards.

So, basically Asterisk is a linux based platform to develop CTI Applications right from low end Analog Phones to high end VoIP. They support host of protocols like their paid counter parts (Dialogic, Synway etc.) SS7, ISDN, R2MF, SIP, Speech Recognition etc.

How does it compare with traditional CTI hardware and Propritary IVR Software ?

Though it claims to be Open Source, low cost but some how I am not convinced it is an alternative of Dialogic, Synaway or other cards. Because at the end of the day, you need proper support for the hardware, plateform while you concentrate on running your business, not the IVR application.

But I am not the right person about giving any expert opinion as I am not using Asterisk. But I have started reading Asterisk and its usefulness in developing and deploying IVR Applications.

I will keep updating about Asterisk here.