What harware we will need if want to run an application made using CT Developer Studio? Do we need to use windows 2000 Server? We need to answer 5 to 10 simultaneous calls, our application is for prepaid calling card airtime recarge.

This Wiki entry will help:

http://www.teleflow.org/wiki/index.php5?title=System_requirements

The section that is most relevant to your question is #3 TeleFlow Standard Server.

Windows 2000 Server would work great, although it is no longer available unless you have an old copy you can use. Windows 2003 Server will work fine too. Be sure *NOT* to get the 64-bit version. It must be the 32-bit version.

You must make sure whatever physical computer you use has room in it for a full-length PCI-X card.

The telephony card I would recommend you get is the Dialogic NMS AG 2000. It supports up to 8 simultaneous calls. You've indicated 5 to 10 simultaneous calls, so if 10 is your actual maximum, you will need two of these cards. If your real maximum is somewhere in the middle, this card will be ideal.

Further, you can start with one card, and add a second later on, if need be. Just be sure your server computer has room for two full-length PCI-X cards.

Than you.

That was really helpfull.

Can I star with a smaller card, maybe one that allws 4 simultaneous calls?
Which one can I use?

Before you do, check what type of computer you are going to be able to get. Finding one that hosts 2 full-length PCI-X cards is going to be a problem as it is. If budget is a concern, you will save money on increments of 4-port cards, and spend all your savings and then some on a wide-backplane PCI-X server.

That aside, you can try one these models, also from Dialogic

D/4PCIUF
D/41JCT-LS

I noticed also, that these cards are now available in PCI and PCIe. I have not tested the PCIe cards, so I cannot vouch for their performance with TeleFlow, but the PCI versions will certainly work. Also, be careful that the type of card you choose matches the bus you get for your computer.

I hope that helps.