Configuration Tasks
10 Cisco IOS Release 12.0(7)T
Fine-Tuning ISDN Voice Ports

Depending on the specifics of your particular network, you may need to adjust voice parameters

involving timing, input gain, and output attenuation for voice ports. Collectively, these commands

are referred to as voice-port tuning commands.

Note In most cases, the default values for voice-port tuning commands will be sufficient.

To fine-tune ISDN voice ports, use the following commands beginning in privileged EXEC mode:

3Router(config-voiceport)# cptone country Selects the appropriate voice call progress tone for this
interface.
The default for this command is us. For a list of supported
countries, refer to the Multiservice Applications
Command Reference.
4Router(config-voiceport)# compand-type {a-law|u-law}Selects a companding type for this voice port.
5Router(config-voiceport)# connection {plar string|trunk
string}
(Optional) Specifies either the trunk connection or the
private line auto ringdown (PLAR) connection. The string
value specifies the destination telephone number.
6Router(config-voiceport)# music-threshold number (Optional) Specifies the threshold (in decibels) for
on-hold music. Valid entries are from –70 to –30.
7Router(config-voiceport)# description string (Optional) Attaches descriptive text about this voiceport
connection.
Step Command Purpose
1Router# configure terminal Enters global configuration mode.
2Router(config)# voice-port {shelf/slot/port:D} |
{shelf/slot/parent:port:D}
Identifies the voice port you want to configure and enter
voice-port configuration mode.
3Router(config-voiceport)# input gain value Specifies (in decibels) the amount of gain to be inserted at
the receiver side of the interface. Acceptable values are
from –6 to 14.
4Router(config-voiceport)# output attenuation value Specifies (in decibels) the amount of attenuation at the
transmit side of the interface. Acceptable values are from
0 to 14.
5Router(config-voiceport)# echo-canel enable Enables echo-cancellation of voice that is sent out the
interface and received back on the same interface.
6Router(config-voiceport)# echo-canel coverage value Adjusts the size (in milliseconds) of the echo-cancel.
Acceptable values are 16, 24, and 32.
7Router(config-voiceport)# non-linear Enables non-linear processing, which shuts off any signal
if no near-end speech is detected. (Non-linear processing
is used with echo-cancellation.)
8Router(config-voiceport)# playout-delay {maximum
milliseconds|nominal milliseconds}
Specifies the amount of time in milliseconds configured
for the playout delay buffer.
9Router(config-voiceport)# timeouts initial seconds Specifies the number of seconds the system will wait for
the caller to input the first digit of the dialed digits. Valid
entries for this command are from 0to 120.
Step Command Purpose