... PBX and IP-PBX 1. Strong interface capacity: can access to PSTN, CDMA, GSM, and IP networks ... .2. Optimized call route: can access to different networks CDMA, GSM, PSTN etc. ... solution to call cost. With IP-PBX, users can make international calls while enjoying local call payment, and ... installed in a user’s computer, the computer can display caller’s name and caller’s number while ...