LANCOM VoIP routers are equipped with multiple ISDN interfaces, which can be used either to connect the device to an ISDN exchange line or to ISDN terminal equipment.
- ISDN-TE interface ("external ISDN line")
- An ISDN interface in TE mode for connection to the ISDN bus of an upstream ISDN PBX or to an ISDN NTBA. This ISDN interface can be used for backup connections over ISDN or as a dial-in interface for remote sites.
- ISDN-NT interface ("internal ISDN line")
- With its ISDN interface in NT mode, the LANCOM VoIP router itself provides an internal ISDN bus. This ISDN interface can be used to connect ISDN PBXs or ISDN telephones.
Ex-factory each ISDN interface is set to TE mode. A cross-over adapter (shipped with the All-IP option) converts it to an NT port. With LANCOM business VoIP routers, this function is controlled via LCOS.
- Multiple TE interfaces provide, for example, up to four B channels as a backup or for dial-in.
- With multiple NT interfaces, for example, a downstream ISDN PBX provides up to eight B channels.
Depending on the combination of ISDN interfaces in TE and NT mode, you need to set up the bus termination, and the appropriate protocol needs to be set in the software. The setting for the protocol allows for the type of ISDN connection to be used (point-to-multipoint or point-to-point).
