Synonymous with hosted PBX and virtual Centrex. Centrex service provided from a network-based carrier-class IPBX platform to which the user organization connects over the public Internet or a private IP network as though it were a remote Centrex central office (CO). See also carrier-class, Centrex, Internet, and IPBX.
A telephone service in which an IP-based PBX is located in the telephone company's facilities. It connects to the customer via the LAN rather than by telephone wires. IP CENTREX offers voice over IP and other IP-based services as well as connectivity to the regular telephone system (PSTN). See CENTREX and hosted VoIP.