... HDLC, and Frame Relay data modes. The board drives both line-side and trunk-side interfaces, including call features.The card ... and powerful interface supporting voice and data transmission over T1, E1, and Primary Rate ISDN (PRI) connections. A low profile, ... , Call Conferencing,Voicemail ,and VoIP Gateways. Interfaces:- 4X E1/T1 interfaces ( E1/T1 selectable) -PCI 3.3V interfaceFeatures:One PRI port ...