CTI (Computer Telephony Integration) Boards, Also known as CT Boards (Computer Telephony boards), is the interface between various IVR software running on the computer and the telephone network. It is normally a PC add-on boards which is installed inside PC/Server Chassis and which is connected to telecom network physically with through E1 or Analog FXO.

With introduction of VoIP communications, CTI is no longer just hardware based, it can also be software and using existing network interface cards in the server of PC. For example, Dialogic HMP 3.0 is software CTI like solution for VOIP or SIP phones. With 3G being introduced, we might see end of CTI boards!

Indian CTI market is getting crowded with new vendors now a days. Gone are the days when CTI boards mean Dialogic. We now have almost all vendors opening shop in India from all over the globe. Many Chinese companies have opened office in India and selling low cost CTI boards in price sensitive market like India.

Here are few new players which have become quite active lately in Indian market:-

1. Sangoma is a Canada based company which has 2 port analog USB based cards to 8 E1 PRI boards. They have also recently launched SS7 boards. They support Asterisk as well as has own API for developing voice applications. Alliance Infotech is their Indian distributor along with ForeMost Systems. All computations are done on the Host PC making their board sizes small. But it also increases CPU usage of the Host PC. Another disadvantage is, they do not provide Echo Cancellation and CPA ( Call Progress Analysis) as a default feature.

2. Synway is Chinese company which has large range of products beginning with 2 port analog USB boards to high density server based media gateways with 64 E1 connectivity! They have low cost, high performance and feature rich boards. They claim, they are now number one for voice logging products in India. They have products supporting both Asterisk as well as own API for developing IVR applications.

3. Donjin is another Chinese company which has analog CTI boards as well as high density KeyGoe Series of products which has 48 E1 connectivity per system! They support Dialogic APIs for their voice boards upto 8E1 which is a major advantage for them as there are many Dialogic based voice application developer in India. Their boards are feature rich as well as much cheaper than Dialogic.

4. Aculab is UK based company and they sell both CTI hardware as well as voice applications. They are not very cheap, but their boards are most suitable for voice portal applications. Recently, India has witnessed rapid growth of voice based value added service (VAS), and Aculab has potential to grow here. ForeMost Systems is their Indian distributor based in Mumbai.

5. OpenVox is another Chinese CTI board manufacturer which are Asterisk based. They have both analog and Digital voice boards. They are also very competitive. ForeMost Systems is their Indian distributor based in Mumbai.

6. AudioCodes is Israel based company which provides TDM and IP based telephony servers for value added services.

Apart from these foreign companies, there are few home grown CTI board manufacturer who provide complete solutions from CTI boards to Voice Applications. Few Indian companies who provide CTI boards are:

1. ExtendIVR : ExtendIVR is majorly known for their IVR platform ExtendIVR, but they also have CTI boards.

2. OZONTEL : Ozontel Systems, based out of Hyderabad has come out with a dual port E1 PRI CARD. It was integrated with Asterisk and comes atleast at half the price of cards which are being imported. Its manufactured within India and hence support is available for both s/w and h/w out of India.

3. Punjab Communications Limited is one of the oldest IVR companies in India which has their own CTI boards.

Though Dialogic is still the biggest CTI vendor in India, but with these new CTI companies, we can expect dominance of Dialogic will reduce and IVR users will have more choice. As per Dialogic, they will soon come out with voice products specific to India which will be aggressively priced keeping mind of these competitions.

Dialogic D/300 JCT-E1 is the entry level board for anyone who needs digital network interface with PSTN network as well as voice resources in the single board. I feel, D/300 board is most used entry

Dialogic D/300 JCT-E1 board

Features of Dialogic D/300 JCT-E1 board

1. Digital Network Interface

It has both E1(2.048MBPS) and T1(1.544 Mbps) support. It supports digital interface network protocols like ISDN PRI, R2MF. ISDN PRI is widely used protocol for connecting CTI board with PBX systems. With D/300 board, it is quite easy to configure it to work with many ISDN variants as per PBX from one country to another or manufacturer.

2. FAX support

Dialogic D/300 board supports both FAX and host based speech recognition. In certain cases, FAX and speech recognition may not work together. It also supports CSP ( Continuous Speech Processing) which offers IVR developers a powerful feature to develop many interesting IVR applications and features depending on the call progress. Speech recognition feature provides IVR developers to develop Speech-Enabled menu for any IVR application.

3. Scalability

Dialogic D/300 supports H.100 connector and it allows it to connect to other Dialogic boards. Inexpensive normal PC can be used to install this board and one PC may install upto 16 boards per machine if PCI slots are available.
With its support for GSM and G.726 bit exact voice coders ( standard for Voice Profile for Internet Messaging (VPIM) , one may develop unified messaging solutions based on D/300 board.

4. Programming

Dialogic D/300 board is supported by many RAD Tools for IVR development. It also supports widely popular GC ( Global Call Protocol) for making many high end, mission critical IVR applications.

Applications

D/300 board can be used to develop any kind of IVR applications. It offers many call related information available with digital network interface protocols. Call bridging available in ISDN PRI is one of the feature which is used to make Click To Call application can be developed.

D/300 board is also ideal choice for starting a voice portal service to start with 30 lines and then increase the lines.

DIalogic has some other models with higher capacity with same features. D/600 and DMV1200 have 60 voice and 120 resources respectively. One may move from D/300 to DMV/1200 without having to make any changes in the application.

Other CTI vendors like Donjin, Synway, Digium too have D/300 equivalent boards. For example, Digium TE122P/TE122B, Synway TEJ Series and Donjin DN300 are Dialogic D/300 equivalent boards with similar features.

I keep getting mails by various people about detecting caller id using D4PCI and Dialogic API. I remember I too had to try hard once and finally contacted Dialogic support for getting ideas how caller ID could be detected using D4/PCI analog CTI board from Dialogic. I think the same procedure should work for Donjin Analog boards as well as any kind of Analog CTI boards, for that matter.

So the steps for detecting Caller ID in D4PCI board is :

1. As soon as you detect RINGING, do not connect or answer the call. But start detecting digit using appropriate API function. For example dx_getdig();

2. Important part is the settings in DV_TPT structure which is used in dx_getdig() function. Here is how I have been configuring:

• End of DX_MAXDTMF should be configured to be length of expected Caller ID length.
• DX_MAXTIME should be configured to be delay between two rings.
• Since DTMF digits for Caller ID are sent together quickly by the PBX, one may take advantage of the option DX_IDDTIME ( Inter-digit Pause).

3. As soon as one comes out of from dx_getdig() function either because of DX_MAXDTMF,DX_MAXTIME or DX_IDDTIME, one should check if Caller ID is detected or not!

So these are the three simple steps for detecting Caller ID using D4PCI board. Here is the C++ code snippet:-

DV_TPT tpt[4];

// Allocate memory
memset( tpt, 0, (sizeof( DV_TPT ) * 3) );

/* Terminate GetDigits on Receiving MAXDTMF Digits, Interdigit Pause and MAxrime */
tpt[ 0 ].tp_type = IO_CONT;
tpt[ 0 ].tp_termno = DX_MAXDTMF;
//tpt[ 0 ].tp_length = MAXDTMF;
tpt[ 0 ].tp_length = digits; // Number of digits of expected caller ID
tpt[ 0 ].tp_flags = TF_MAXDTMF;

// Terminate dx_getdig function after 3 second Interdigit pause
tpt[ 1 ].tp_type = IO_CONT;
tpt[ 1 ].tp_termno = DX_IDDTIME;
tpt[ 1 ].tp_length = 30; // Gap in betwwen digits
tpt[ 1 ].tp_flags = TF_IDDTIME;

/* Terminate GetDigits after 8 Seconds */
tpt[ 2 ].tp_type = IO_EOT;
tpt[ 2 ].tp_termno = DX_MAXTIME;
tpt[ 2 ].tp_length = 80; // Maximum time
tpt[ 2 ].tp_flags = TF_MAXTIME;

if (dx_getdig( voiceh_handle, tpt, &(dtbuf),(unsigned short)ASYNC ) == -1 )
{
printf(“getdtmfs return 0x%X\n”, ATDV_LASTERR(pline->voiceh));

}

So here are few facts I have realised:-

1. D4PCI board ( or any analog board in that matter ) may not detect caller ID all the time completely (all the digits) all the time. It has nothing to do with the Dialogic CTI board though. The reason can be explained as below :

Normally, caller ID is presented in the form of DTMF ( Dual Tone Multiple Frequency) digits after the first ring and before the second ring.

I have observed that, some times, analog board fails to detect the first ring and detects the ring from the second ring only. It this case, any CTI application would miss the caller ID completely. Some other times, the analog board (D4PCI or equivalent analog CTI boards) would detect the ring at the end of first ring cadence which may result in missing first few caller ID digits.

So, detecting caller id perfectly using analog board may depend on PBX being used. If any one knows any better technique, it will be great to share here.

There are many disadvantages of using analog CTI ( Computer Telephony Integration) cards. Apart from that, digital CTI boards offer many advantages over analog CTI boards and I would like to list three main reasons why one should upgrade to digital CTI boards from analog ones.

Even in India, E1 connectivity or PRI lines are easily available from any telecom service provider and it is much cheaper. And with, many new CTI manufacturers are offering high quality digital CTI boards which are easily available.

Here are three reasons :-

1. Dialed Number Identification ( DNI Facility)
Digital boards provide DNI ( dialed Number Identification) which is not available in analog CTI boards. DNI can be very useful. It provides options for separate CTI applications depending on the DNI detected. The same interactive voice response application could play different welcome prompts as per DNI. For example:- A digital interface with Telephone exchange may offer 30 different numbers, and one common number for all 30 lines. Now depending on caller dialing one or groups of numbers, a separate greetings, separate call flow can be implemented in the same CTI application. There would be flexibility to change, modify these numbers without having to change any physical lines.
DNI can also be used for shortcut in menu options. For example, there are 4 kinds of complaints in a company. Four separate numbers could be used for each of the complaints saving callers time to choose a complaint through menu. This can greatly increase usability of any interactive voice response system application.

2. Quick connections
Digital CTI boards uses digital protocol for quick call setup and quick information exchanges. So, any call can be connected quickly. But n analog, it order to CTI boards, one has to wait two rings before the call can be connected. Many of the times, analog CTI boards may not detect CLI at all. Any irate customer gets more irritated when her call is connected after 2/3 rings. It also saves time and handle more calls. So the throughput of digital boards is more than analog CTI boards.

3. Disconnect Problems
Analog CTI boards need to train on varius disconnect tones which may vary from one PABX to another. It takes time to setup detection of these various tones like Busy Tone, Engage Tone, Disconnect Tone, Dial Tone. Also, it takes some minimum time to detect any of these tones. So, analog CTI boards take time to dial out, disconnect.
During outbound calls, it is not easy to detect if called number has picked the call or not. Many people use here voice activity detection as ring back tone does not work with accuracy. With digital CTI boards, all these problems are removed. This not only saves time, but it increases efficiency, result in more number calls.

There is one benefit of having analog lines. out of many analog lines, if one cable is cut, remaining lines will work, in digital, it is only one wire, so one cable is cut, whole of your lines or at least minimum 30 ports would go down.

So, if you are still using analog CTI board, consider upgrading to digital CTI boards now!

I think, analog CTI boards most problematic to configure other than simple incoming or inbound IVR Software. They are dependent on switch or PBX connected to them for many basic IVR functions, call operations. I am trying to list here the problems I had been facing while using analog CTI boards:-

1. Disconnect
2. Dial Tone
3. Dial out
4. Caller Id

1. Disconnect
You need to ‘define’ the disconnect tone to your IVR application so that it can detect disconnect. This disconnect tone may vary from PBX to PBX. Dialogic has a tool PBXpert to detect various analog tones like dial tone, disconnect tone, busy tone, ring back tone etc. With CRBT ( Caller Ring Back Tone) being popular now a days, detection of ring back tone has just become more difficult.

2. Dial Tone
Dial tone also varies from one PBX manufacturer to another. This dial tone becomes very important when you make an outgoing call. IVR application may be unable to make outgoing call if it fails to detect dial tone. Though there are ways to dial out without detecting dial tone or learn dial tone and feed in IVR application, it is still not easy.

3. Dial out
Once successfully dial out, it may not be easy to detect if dialled party has picked up the call. Many people use Call Progress Analysis to detect, if person has picked up the call. But I always think, it is not easy or it does not work accurately all the time.

4. Caller ID
Unlike in digital CTI boards or Digital Telephony interface, caller ID detection is almost a pain and it may not work accurately all the time. Normally, in analog interface with PBX, the caller id is sent by PBX in DTMF form after first or second ring. So, it is really cumbersome to detect Caller ID.

Digital CTI boards with digital interface does not have the above problems. So it would be nice if one can avoid using analog CT boards and use digital boards. Though digital boards are costlier, but now a days there are many CTI vendors which have digital CTI boards which are priced very competitive.

I have thought of an arrangement to avoid using analog CTI cards. Though it may make the IVR system costlier, but most probably, it will be good arrangement in terms of future enhancements, more features. My thinking is to use use a EPABX with PRI card. the CTI board will be connected to EPABX through E1 connectivity and use ISDN PRI protocol. Commonly used and widely available. In turn EPABX may have CO lines from telephone service provider ( analog lines which other wise you wold have connected to CTI board directly). This kind of EPABX may cost less than Rs. 150,000/-

Now, when price of 4 port CTI boards starts with Rs. 10,000/-, investing another Rs. 150,000 on a EPABX and another Rs. 30,000 for a digital CTI board, may not make sense, honestly! But there are some benefit of using this kind of arrangement for for specific IVR application and outbound IVRS is one of them, considering the cost of hiring a E1 link from telephone service provider.

But, the problems I have listed above can be solved by smartly writing your IVR software. In fact, they must be routine problems for many IVR developer, unfortunately no document is available on net, at least I could not Google it. And I am yet to write a smart IVR application for analog CTI board as I started my IVR software development with Dialogic D300 board and R2MF protocol!

Dialogic needs no introduction, so the Dialogic D4 PCI board. Synway and Digium too have D4 PCI equivalent Voice Boards. While both Digium and Dialogic boards uses PCI slots, Synway 4 Port Board uses a USB port like modem.
I have been thinking about comparing these three boards using few common parameters.

1. Ease of Installation
2. Easy availability and price
3. Software API Support
4. Technical Support
5. Developer Base
6. MTBF ( Mean Time Between Failure).

1. Ease of Installation
My ranking would be 1. Synway 2. Dialogic 3. Digium. Synway uses USB connector, so one does not have to open the cabinet of PC to install it! This I find to be a major advantage over Dialogic and Digium. Though installing the cards inside the cabinet may make the set-up neat and clean, but ease of installation seems more important here.

2. Easy availability and price
On price, Synway scores much higher than both Dialogic and Digium. And all of them are now a days easily available in almost all countries. Dialogic may have a little edge over the other two, Synway and Digium here.

3. Software API support
My ranking would be : 1. Dialogic 2. Digium 3. Synway. Dialogic is definitely ahead of the other two when it comes to software API supports. Dialogic has vast resources as well as Dialogic-trained manpower all over the world. Dialogic has very well developed APIs which can be used in three major operating systems like Windows, Linux and MAC OS. While Digium has open source Asterisk on its side, Synway claims to support all Dialogic API.

4. Technical Support
My ranking will be again 1. Dialogic 2. Synway 3. Digium. I have not worked with Digium, so I am relying on information available on internet and information by my friends. I have first hand experience with both Dialogic and Synway. Dialogic has very good technical support team as well as vast resources. Dialogic has a very active support forum www.dialogic.com/den. Though both Synway and Digium has active forums, but I think Dialogic scores over them.

5. Developer Base
No credit for guessing it correct, it’s Dialogic! There are many Dialogic developers in the world! Also there are many third party visual development tools based on Dialogic boards! One may check this tools for developing IVR Software which I posted earlier. Digium should be placed at second and Synway at third. But developer base for both Synway and Digium are increasing. That includes me too .

6. MTBF ( Mean Time Between Failure) :
I have seen Dialogic mentioning MTBF in their data sheets which is more than 5 years! So, I am quite positive that Dialogic must come at top here. Overall, now a days all boards are equally good!

So, overall, Dialogic may have an edge over other two CTI boards! But in a price sensitive market like India, Synway might find more supporter than Dialogic.

High-End digital CTI boards for a voice portal is not cheap! In fact some of them cost as much as a Honda Civic car in India. So, choosing a right CTI Board for your Voice Portal may not be easy, that is until you read this article .

So, how to choose a CTI Board for your voice portal application ? There are few parameters using which one should choose CTI Board for Voice Portal:-

1. Number of Expected Simultaneous Calls
Most important factor to consider! If you expect simultaneous calls to be not more than four, buy any four channel analog card. But than, most probably it will not remain a voice portal! Ideally, if one should choose a CTI board with 50% more capacity than the expected number of glutenous calls. if some one expects 10-15 calls, he should choose one 30 port Digital CTI board.

2. Time to connect a call
Time taken for connecting a call when an user call is important! It depends of the interface the CTI board supports. For example, CAS R2MF connects much slower than SS7 or ISDN PRI. One will hear “teent teent teent” sound after dialing the Voice Portal before connection. Normally quick and instant connection to Voice Portal is desired.

3. Interface With Switch Support
The type of interfacing with switch of Telecom Provider is important parameter to consider. Many Telecom Service Provider may not have CAS or ISDN protocols on their switch or they may not be willing to provide that connectivity to Voice Portal operators. So, one must consider about available protocol with Telecom Provider before deciding on a CTI board. Interfacing with various protocols is responsible time to connect of calls. SS7 cards are costlier than ISDN PRI or CAS R2MF boards, connects calls almost instantly. And some CTI Manufacturer like Dialogic does not have a combined board which has both Voice Processing and SS7 Signaling so far! This kind of arrangement has its own advantage over combined CTI boards. For example, one can have add more Media Processing (Voice Processing) Boards while keeping one signaling board in one system. Also combined (Signaling and Media Processing) CTI boards do not come in low density configuration, they normally have 8 E1 or more. 4E1 meaning at least 120 simultaneous calls!

[ad#image-large]

3. Scalability and IVR Software
This is another aspect one should not ignore. If the Voice Portal becomes popular, which is the main aim by any Voice Portal Operator, so the CTI Boards should have scalability feature where increasing number of simultaneous calls should not make existing hardware redundant, or make IVR Software obsolete. Separate boards for signaling and media processing is recommended for scalability. IVR Software should be designed such a way that, it can handle more voice resources without having to re-develop the IVR Software.

4. Support for the CTI Board
Availability of development support as well as quick 24 hours support for any problem in the CTI hardware is a must! Every minutes of downtime of Voice Portal, the operator loses revenue! So, one should choose a CTI vendor which can provide quick support or quick replacement of CTI hardware in case of CTI board failure! Also, CTI Vendor should have active forum to discuss various issues and should have good number of third party developers!

5. Cost
Cost is very important, well for everybody! But, one should not compromise of quality of CTI cards for cost.

My Favourite and Recommended CTI hardware:

1. For 30 to 120 simultaneous Calls.
Start with Dialogic D/300 JCT or DMV1200 card. They have ISDN, R2MF protocol, good support, quite tested CTI board. Many developers have written IVR Software on them! Dialogic has good support, active forum, large number of developers. But since they are the biggest CTI vendor, they may not provide you with a demo card for development of your Voice Portal!
These boards can be even used with Dialogic SS7 Signaling boards.

2. For 240 or more simultaneous calls
1. Synway SHD-240D-CT/PCI
Good Value for money, good support. Built in Signaling and media processing. Cheaper than Dialogic equivalent.
2. Dialogic SPCI4/SPCI2 and DNI2410
Awesome combination, great scalability, very good support and large number of developers as well as very active forum. Cost is almost double that Synway though!

Arguably, Dialogic D4/PCI analog card must be the most widely used CTI card in the world! Also, most probably again, all 4 Generation Visual Tools for developing IVR Application supports this Dialogic D4/PCI CTI Card.

This card is easy to install, very feature rich, and has many advanced call processing feature. The most problematic part of any analog card s detecting engage tone, busy tone, ring back tone, apart from detecting Pulse Dialing! Amazingly this card has all those call processing feature which can be utilised effectively to solve these problems.

For those who are interested in know complete details, click here.

Here are few tips about using this card:-
1. Find out if your EPABX/Telecom Service provider has enabled Loop current drop at end of call. If not, ask them to enable so that you do not face Call Disconnect Not detecting problem. ( I feel, this is the most widely encountered problem by all IVRS people.)
2. You must create TSF file using PBXpert. This utility comes with Dialogic System Release, all versions. This tool makes few incoming/outgoing calls with two extension lines ( if EPABX) and train itself to detect the Engage Tone, Busy Tone and disconnect Tone, Ring Cadence etc. This step is very important.
3. To make your life easier, check for various PRM files in dialogic directory.

Finally, if nothing seems working, join www.dialogic.com/den/ and shoot your question in the forum. Or you can contact me.

Speech recognition in IVRS has become more of a necessity after mobile phones have arrived. POTS ( Plain Old Telephone ) System have telephone instrument with proper keypad along with head-set. Procedure of calling is suitable for pressing DTMF based interaction with IVR System!

You normally lift the headset with left hand, dial pressing keys on telephone instrument using your right hand. So, when IVR is connected and you are listening to the voices by IVR System as well as pressing keys! While in a mobile phone, the tiny instrument itself is head-set, so when you are listening to IVR instructions, it is almost impossible to press keys without removing from your ear and looking at keys! The one solution is to use ear-phone or blue-tooth powered wireless headset!

Most probably, this has given prompted IVR developers as well as CTI vendors to come out with speech recognition for IVR Input. Though, speech recognition has evolved a lot, still speech recognition can not claim to perform 100%. This happens mainly because of pronunciation, accents of language from one region to another.

There are many speech recognition engines available. Nuance, Loquendo, Microsoft, Spinvox etc. are few companies which provide speech recognition engines on various technologies.

IVR with speech recognition capabilities are supposed to more advanced and suitable for mobile user, but it is actually very difficult to predict if the IVR application and speech engine will be able to recognise speech command properly. But IVR with Speech Recognition has been on the rise and every IVR Company now a days provide speech recognition. CTI vendors too support speech recognition in their hardware.

But still many people like me, will prefer to use DTMF for giving command to IVR as it sounds more technical. Most probably some people will take time get used to the idea of commanding some invisible machines by speaking!

Recently I had successfully configured Synway SHD-240D-CT/PCI ( PDF File). I thought I would share my experience of configuring Synway SS7 card and configuring Dialogic SPC DNI2410 cards.

First, we are very grateful to Synway for giving us the demo card for testing and development our application. The card was given to us for a month, but it ended with us for more than 6 months! Here is chronicle of events how we configured SHD-240D-CT/PCI card using one SS7 link, from BSNL ( Bharat Sanchar Nigam Limited).

1. Downloaded the latest driver for SHD-240D-CT/PCI. It was easy to locate the driver and download.
2. Installed the driver on our IBM X3400 Server with Windows 2003 Server. Quite easy!
3. Then I wrote an email to tech support of Synway informing we are new with Synway Card, so we need some step-by-step instruction of getting started.
4. Within 12 hours, they sent back documents with screen shots which explains clearly what steps to be taken. No editing of .txt or.cfg file!
5. I followed the instructions and wow, surprise! It actually worked! I mean I could see the Network Connected MTP messages being exchanged in the log! And try find out some STEP by STEP guide of getting started of any Dialogic cards for a newbie!

But no calls were landing! So I shot of an email again. They asked for remote access! after remote access it took one hours by the tech support person to land calls on the card and we could see CLIs, call statuses etc.!

The configuration was over in 5 days time! Actual time spent was less than 10 hours. Bottom line is, we could configure the Card in 10 hours.

We also configured Dialogic SPCI4! It took us 2 months to configure with same link, same operator! Dialogic event sent one engineer at our site and he spent one full week, it was finally configured though! Here are few difference we noticed:-

1. In case of Synway, all parameters have visual configuration tools. While in case of Dialogic, they have only .txt files to be edited using editor. No visual tool.
2. Synway has all monitoring/debugging facility built in on the configuration tools itself. While in Dialogic, one has to execute different EXE files for different logging of events and than debug!
3. It was easy STEP by STEP instruction available for Synway, but Dialogic has too big software, difficult to remember executable files, configuration files.

My overall experience is, configuring Synway was much faster, easier, more user friendly than Dialogic. We are yet to put the Synway Card on live system. We are still running our IVRS Application on SPCI4 and DNI2410 ( The Royal Combination for Voice Portal) and it is handling around 10 to 12K calls daily on our voice portal. We have been quite happy with the performance of the cards. How Synway Card performs here will be interesting.

Now the cost part. Single line is, Synway costs half the price of Dialogic with almost same resources and features. I will try to prepare a comparison chart between Synway SHD-240D-CT/PCI and Dialogic SPCI4/DNI2410 in my next posts!