Specifications

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Catalyst 4224 Access Gateway Switch Software Configuration Guide
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Chapter 6 Configuring VoIP
Configure Voice Ports
• FXO—The foreign exchange office interface uses a RJ-11 modular telephone
cable to connect local calls to a PSTN central office or to a PBX that does not
support E&M signaling. This interface is used for off-premise extension
applications.
• E&M—The E&M interface uses an RJ-48 telephone cable to connect remote
calls from an IP network to PBX trunk lines (tie lines) for local distribution.
It is a signaling technique for two-wire and four-wire telephone and trunk
interfaces.
Configure FXS or FXO Voice Ports
Under most circumstances, the default voice port values are adequate to configure
FXS and FXO ports to transport voice data over your existing IP network.
However, if you need to change the default configuration for these voice ports,
use the commands outlined in Table 6-3, beginning in privileged EXEC mode:
Table 6-3 Commands to Configure FXS and FXO Voice Ports
Task
Required or
Optional Command
Step 1
Enter the global configuration mode. Required
configure terminal
Step 2
Identify the voice port you want to
configure, and enter the voice port
configuration mode.
Required
voice-port slot-number/port
Step 3
(For FXO ports only) Select the appropriate
dial type for out-dialing.
Required
dial-type {dtmf | pulse}
Step 4
Select the appropriate signal type for this
interface.
Required
signal {loop-start |
ground-start}
Step 5
Select the appropriate voice call progress
tone for this interface.
The default for this command is us.
Required
cptone country
Step 6
(For FXS ports only) Select the ring
frequency (in Hz) specific to the equipment
attached to this voice port and appropriate
to the country you are in.
Required
ring frequency {25 | 50}