Current trends
One of the latest trends in PBX development is the VoIP PBX, also known as an IPBX, which uses the Internet Protocol to carry calls. Most modern PBXs support VoIP.ISDN PBX systems also replaced some traditional PBXs in the 1990s, as ISDN offers features such as conference calling, call forwarding, programmable caller ID, etc.
However, recent open source projects (in particular, VoiceLogix, Asterisk and SIPfoundry) combined with cheap modern hardware are sharply reducing the cost of PBX ownership.
For some users, the Private Branch eXchange has gone full circle as a term. Originally having started as an organization's manual switchboard or attendant console operated by the telephone operator or just simply the operator, they have evolved into VoIP centers that are hosted by the operators or even hardware manufacturers. These modern IP Centrex systems offer essentially the same service, but they have moved so far from the original concept of the PBX that the term hardly applies at all.
Even though VoIP gets a great deal of press, the old circuit switched network is alive and well, and the already bought PBX's are very competitive in services with modern IP Centrex's. So currently we have 4 distinct scenarios in use:
PBX (Private and Circuit Switched)
Hosted/Virtual PBX (Hosted and Circuit Switched) or traditional Centrex
IP PBX (Private and Packet Switched)
IP Centrex or Hosted/Virtual IP (Hosted and Packet Switched)
Since in reality people want to call from the IP side to the circuit switched PSTN (SS7/ISUP), the hosted solutions usually have to maneuver in both realms in one way or another. The distinctions are seldom visible to the end user.
posted by Jack @ 9:23 AM
