I have a running, working set-up of the QTelNet softswitch. I am using it to play the IVR prompts, manage prepaid and post paid accts, and as a bonus you are allowed to modify the web user interface and make any changes you want! I have modified mine to allow for export of CDR based on account number. What else could you ask for??
As far as the rest of your questions, here you go:
1. what is the database behind the scene for call management and routing?
it supports Excel, Sql and MySql
2. What version of Gatekeeper use?
it is not a gatekeeper. what it does is act as a signalling proxy. in other words, acts as a giant phone book that can route calls and authorize users based on CID, IP, prefix, etc and send the call to whatever destination you want. it does not matter if an incoming sorce is H323 and the outgoing entity is SIP. It works! same for the other direction.
By being a signalling proxy and not a unit that actually hosts the call on the inbound and outbound legs, it does not have to do very much work for each call. therefore, the number of simultaneous calls is not limited by the translation process. It is however limited by the licence you purchase.
3. What is the operating platform?
mine is currently running on win2K. it is supported by win2k pro, win2k server, winXP and RedHat Linux 7.2
i believe the rest of the questions are answered above.