Features: One PRI port 30 channels Hardware DTMF detection Conference Bridge PCM bus connectors (PCM30, PCM64, PCM128) 4 dual-color LEDs (layer 1 state indicators) Active channel switching (across multiple cards over the external PCM bus) PRI ISDN protocol stack Suitable for 3.3 volts and 5.0 volts 32 bit PCI 2.2 slots Application: ISDN PRI PBX ISDN least cost router Voice over IP PRI gateways VoIP integration of ISDN equipment PBX to PBX trunking IVR -EuroISDN -AT&R 4ESS -Lucent 5E -National ISDN2