17
•An FXO (foreign exchange office) interface connects local calls to a PSTN central office or to a PBX that does not support
E&M signaling. This is the interface a standard telephone provides. Ports on this VIC are pink.
•An E&M is a signaling technique for two-wire and four-wire telephone and trunk interfaces. The E&M VIC connects
remote calls from an IP network to a PBX for local distribution. Ports on this VIC are brown.
•A DID is a service offered by telephone companies that allows external callers to dial an internal extension directly, without
operator assistance. The VIC connects remote calls from the PSTN to a PBX for local distribution.
•The ISDN BRI NT/TE VIC provides a client-side (terminal equipment, or TE) ISDN S/T physical interface for connection
to an NT1 device terminating an ISDN telephone network. It can also be configured to provide a network termination (NT)
interface with phantom power. Each of its two ports can carry two voice calls (one over each ISDN B channel), for a total
of four calls per ISDN BRI card. At present, the ISDN BRI VIC does not support ISDN devices such as digital telephone,
fax, or modem.
Figure 11 shows a typical VIC.
Figure11 Voice Interface Card
You should install and cable the VICs before you perform the software configuration tasks that follow.
Configuring FXS Interfaces
This section explains how to configure ports on FXS VICs that connect directly to a standard telephone, a fax machine, or a
similar device.
Figure 12 shows a basic voice network. A small business uses a Cisco 1760 router (named West) to provide telephone and fax
connections among employees in its office. Two of these telephones are connected to an FXS VIC port in the West router.
Figure12 Basic Voice Network (West Router)
Note You can name your router by using the global configuration hostname command.
(For information about port numbering, see the “Voice Port Verification” section.)
10694
SEE MANUAL BEFORE INSTALLATION
VIC
E&M
IN USE
IN USE
1 0
VIC port 1 VIC port 0
408 555-3737
408 555-4141
FXS VIC
0/0
FXS VIC
0/1
West IP cloud
22634