IP PBX with 4 to 48 FXO ports

Embedded IP PBX with 4,8 or16 FXO analog ports, and 8,16,24 FXS local extensions; and 60 IP users in local or remote, support SIP and DDNS, Can be working under NAT; based on Linux OS, GUI for management; The RT20 is an All-in-One converged communication system for small and mid-size offices, home offices and branch offices. It provides the connectivity to not only traditional analog trunks and analog extensions, and but VoIP based SIP trunks and remote extension as well. Using VoIP it allows calls from one location to another over internet or VPN, it allow extensions to be boundled with cell phone, and it also directly integrates with VoIP service provider networks. Depending on configuration when it is purchased, it supports from8 to24 local extensions, 60 remote extensions, and8 to16analog trunks. With its flash memory capacity, RT20 alsosupports built-in IVR, calls records, and downloads for color ring back tones.