Predictive dialing

How can we get this predictive dialing happening with Asterisk? Any clues on this. cheers

I starting 20 seat call centre using Astriesk PBX system. Its going to be totally Ip based. Wondering which predictive dialer is better, Gnudialer/ Indosoft/ sineDialer?

Has anybody used this. What are best hardwares to use. Its going to be only telemarketing.

Thanks and Ni Sa bula!



Both are Asterisk-based, GPL, free and in production at many companies.

I highly suggest Vicidial. Its good, easy to maintain and flexible.

There is indosoft and sineDialer. Are they any good.

VICIDIAl does not do predictive dialing though. why its better?

I was thinking Gnudialer would be best.

VICIDIAL does in fact do predictive dialing, and does it quite well…we have been using it in power dialing mode for almost 9 months, and other than some hardware issues, it has performed admirably.

that, and the developer, matt florrell, is a very nice guy and will drop everything to help you…

EDIT: but that doesn’t mean you should call him and ask him to drop everything if you’re having a problem (sorry matt)


If you are looking for a scalable robust commerical solution over Asterisk.
Look at DACX Contact Center Suite from Drishti.

It is running at more than 70 centers across India and philippines.



I have 100% decided to use VICIDIAL now. As for the server for 20 seats I am thinking to buy one of those server machines (blade, opte…, xeons). (Thinking to have 3 servers) good one(P4 3 2GB ram)

I have 2 normal Pcs (that is idle) with me that is P4 2.8ghz 512RAm. As for as server is concerned , do I have to get those proper servers that has some other special things. Can normal Pc become a server. I can put more Ram on those.

Why 3?

1 server for Asterisk
1 server for VICIDIAL/ web/php/mysql
1 server for web/archives (for recording purpose and backup and for file sharing)

All Linux (slackware)

After this I am also bit concerned about which OS shall I use for client Pcs

I prefer windows since most people are using windows buit if we choose Linux will it be better or it doesnt make any difference?

I was thinking if I can get clone computers for P3 without any OS at very low cost I could switch to linux.

Will windows xp profession service pack 2 run better in P3 or Linux or which ever windows is better?

After this few issues I can go and buy the required hardware. Anybody who knows where I can get cheaper clone computers please let me know.

cheers and thanks

Three servers should work well for you in most conditions. Yes, you can use regular PCs for your servers.

Are you going to be using T1/E1 lines or VOIP trunks?
If VOIP trunks then what codec are you planning to use?

What dial level are you planning on calling out at(lines per agent)?

As for client desktops, we use almost all Linux at our centers(We are switching to linux at all of our call centers). They take much less time to maintain since they have no major virus issues and most people don’t know how to load spyware or other junk on them. Then of course there is the fact that you have no licensing issues and the OS costs nothing. I would guess that Linux would run better on P3 workstations than WinXP would.

Just a suggestion for you as I saw someone ask if you were going to use T1/E1 etc. ** Use ISDN PRI ** that is if you are going to use standard telco trunks. If you are going to really get up to speed dialing you will run into fewer hiccups and especially hung channels and glare conditions if you do this. VoIP channels are another issue completely. Just keep in mind simple standard and fast is better either way.

You may want to go take a quick look at the stuff the people at Presence put together. It has a couple of advantages that the others do not have. For one, it is simple to deal with… or at least the easiest so far. If you don’t have a big staff and don’t want to be tweaking until the early hours of the morning it might be a better idea. They are also better integrated. Since they are commercial I looked at their pricing and it seemed very competitive compared to the big guys that I am used to working with. * I have done work for really huge centers as well as my own small center. It is a very serious proposition considering the time required to make something work versus the money I make versus the amount I spend.

I differ in my opinion on the client Desktops. If you like windows then use windows. If you like Linux or MacOS the use Linux or MacOS. If you want to use pen and paper the use that. It all comes down to what you are comfortable with. In some cases you will have no choice. Your desktop OS will be specified by your applications. (I know you could use an emulator or the like) Virus and the rest can be controlled. For instance my agents can only go to specific sites and use specific email clients and so on. The rest is restricted. The result is I have never had a problem. I will say this. Given the choice I might switch everyone to Linux or better yet FreeBSD or Solaris just because I comfortable with it. The licensing alone for windows leaves a bitter taste and I would rather give that money to one of the Linux or BSD groups.

One last note… Depending on what you are doing with your DB in conjunction with Asterisk dial plans you may want to increase memory.

In any case, Good luck! Dialers, even though they have come light years since the early years can still be a pain in the neck. Especially when you are working with small numbers of agents.

-nxn (Nicholas)

What is the per seat price for a full Presence CRM system(It looks like the CRM, Scripting, routing and recording components are all sold separately)?

From the small amount of information I can gather from their website, it seems like the Presence CRM Optimizer Voice (Dialer) only works with Windows clients because it requires ActiveX, is that the case?

A very good questions.

I will use purely VOIP Trunks with I Mbps private lease line from my carrier. (havent decided which bandwidth will be o.k, still deciding)
We were using G711 codec (xlite) when making calls manually with 5 agents. the sound was very good quality but was sucking lot of bandwidth. Internet is very expensive in Fiji at the moment. It cost around $US 3000 for 1 meg link. I was thinking about getting 2 since G711 needs arounf 64kbps for each user.

After quite of bit of research I found this G729a codec which takes around 8kbps which is really good. I dont know the voice quality yet coz this is also very important issue. I was thinking to use SIP based coz I found a VOIP provider in Australia (where we do lots of calls) who can give me a very good deals. Unlimited local and National calls cost $AU50 per month per number that is really cheap if we make thousands of calls. BUt I dont think they can support IAX which would have been better. If I can find similer deal with anyone whos got IAX then I will go for it.

I am still searching around any better way of doing this and if you have any idea or suggestion please let me know. I want to use less bandwidh but have quality call. Have you tested G729a codec?

As fur as dial plan is concerned I havent decided yet. But I guess if I am doing predictive dialing then I need 2-3 numbers per agent. What would you recommend?

cheers man.

Those small island internet monopolies are pretty bad, I was once quoted $30,000/month for a 4Mb link in Antigua from their telco monopoly, but here in the US we have hundreds of providers and can get 1Mb links for $700/month at most.

With VOIP bandwidth you need to remember to include signalling and buffer overhead in with your calculations. G711Ulaw while the audio takes up 64k actually takes closer to 72k when used in a VOIP connection. Also, you need to know that with SIP you are sending separate signalling and voice streams resulting in more bandwidth usage for the same number of conversations as compared with IAX which will send all data and voice over the same stream resulting in less bandwidth usage.

I usually recommend GSM since it takes much less CPU than G729 and is still fairly good compression and doesn’t require a restrictive usage license.

As for your dial level, That depends entirely on your leads and the campaign you are running. I have set up systems where customer service agents call back customers and they never need to dial over 1.2, and I have set up campaigns where we had to dial at 5 lines per agent to keep the agents on the phone.

thanks for that matt

Regarding the GSM codec will the quality going to be good. Good for telesales? What I might do is test it when I get the system ready and see whats good. But since you have set up plenty of centres I guess you know are right.


We currenly use GSM in several locations and it is good enough for telesales, but not all termination providers support it so you will have to ask your potential providers to see if it is an option.

I would recommend trying several accounts from different termination companies since they all vary in network and sound quality depending on what network you are on.

thanks for that

Just regarding the client Pc how lowest can I get. I was thinking of getting P3 500Mhz . Can P2 work in client Pc?

what would you think is better for 20 seats?


The lowest we have installed in production with is a PIII 500MHz and 128MB RAM. We have tested as low as an AMD K6 400MHz, but I would not recommend anything below a PIII/500 with 128 MB RAM.

I would assume that a P2 would work, but it would have a slower response to data being updated on the screen, and you must make sure you have enough RAM so that it wouldn’t get into swap space and a newer/faster hard drive which can improve overall system speed.

hi Matt

I am just wondering why you have choosed slackware compared to others. Like Debian.

Its better for vicidial?

Its nothing important just wanted to ask.

Slackware is a very base-level Linux distro. It fits on a single CD which illustrates that pretty well as compared to RedHat or Suse which use 4 CDs for a simple install. The other issue is that Slackware doesn’t load lots of custom utilities or applications that mess with process priorities.

Also we did some performance tests of Slackware against Redhat and Slackware performed a few percentage points better.

I also prefer to install applications from source as opposed to using packages or a package management interface.

Slackware is very basic, installs on all hardware I’ve ever tried to install it on and installs in very little time.

I didn’t see on Vicidial’s site how they deal with the US “2 second” compliance rule for passing calls to an agent within 2 seconds of the far end saying hello. Does Vicidial support this? If not, do any of the other Asterisk based GPL dialers?



The “2 second rule” is part of the USA’s FTC safe harbor provisions and is supported in astGUIclient/VICIDIAL 1.1.12 which will be released this week. It is also present in the snapshot releases of VICIDIAL which have been out for the last month.

It works as a timer from pickup, we usually recommend 5 seconds from receiving of Answer signal from the carrier(which includes the customer saying “Hello, Hello”), but you can set it to whatever safe_harbor_timeout that you like. You can also customize the safe_harbor audio message to be whatever your want it to be.