... IP users Billing, MOH, IVR, Recording All-in-One SIP IP PABX for SOHO useressupport 4 to ... , 3-way-conference; Embedded SoHo IP PBX phone system with 4,8 or 16 FXO analog ports, and ... for management; The RT20 is an All-in-One converged communication system for small and mid-size offices, home ... With its flash memory capacity, RT20 also supports built-in IVR, calls records, and downloads for color ring ...