Cisco Voice/fax module-expansion slot-ISDN BRI ST-4 digital port(s)

This 4-port BRI voice and fax expansion module has ports that are configurable for NT or TE mode. This module allows connection to an ISDN S/T network by replicating either the network side or the terminal side. In NT mode the ports replicate the PSTN interface to a PBX that is compatible with European Telecommunications Standards Institute (ETSI) NET3 and QSIG switch types.