Greetings, I am progressing well with this great product, the *. SIP to SIP calling, Vocal to *, Voicemail all in the past. Did Iconnect, FWD etc. Also, purchased couple of FXO cards and did zaptel as well. It's time to get to h323 now. Read the mailing list for H323 and OH323 etc. need some help to where to start. Requirement is very simple, SIP calls need to be routed to a third party gatekeeper for PSTN termination. I do not want to start a debate on h323 vs oh323, just want to know the limitations and capabilities. 1) How many simultaneous calls can be made through a h323 driver (I know it is a limitation of the linux box but I need to know whether these chan drivers have any such limitation, capacity or something) ? 2) Support of CODEC - Which driver support which codec ? 3) Documentation - I know this is open source, but for a starter which driver provides better doc support 4) Configuration - Which one is simpler and easier, again any pointers other than readmes., Wiki and John Todd was my reference points for all the above, but cant find any h323 stuff there. Thanks in advance for your help. Cheers Sathya