Optional Commands for the Configuration of VoIP
Command Description
Gatekeeper(config-dial-peer)# (Optional) This command chooses the
answer-address string inbound dial peer based on the callingnumber.
Gatekeeper(config-dial-peer)# (Optional) This command chooses the
incoming called-number string inbound dial peer based on the callednumber,
to identify voice and modem calls.
Gatekeeper(config-dial-peer)# (Optional) This command is used to
dtmf-relay [cisco-rtp] configure the tone that sounds in response
[h245-signal] to a pressed digit on a touch-tone
[h245-alphanumeric] telephone.
Dual Tone Multi-Frequency (DTMF) tones are
compressed at one end of a call and
decompressed at the other.
Be aware that if you use a low-bandwidth
CODEC, such as G.729 or G.723, the tones
can sound distorted, which may lead to
problems. The dtmf-relay command transports
DTMF tones generated after call
establishment out-of-band. It uses a
method that sends with greater reliability
than what is possible in-band for most lowbandwidth
CODECs.
Without DTMF Relay, calls established with
low-bandwidth CODECs may experience
trouble accessing automated telephone
menu systems such as voice mail and
Interactive Voice Response (IVR) systems.
A signaling method is supplied only if the
remote end supports it. Options are the
Cisco proprietary Real Time Protocol
(cisco-rtp), standard H.323 (h245-
alphanumeric), and H.323 standard with
signal duration (h245-signal).
Gatekeeper(config-dial-peer)# (Optional) This command indicated the
fax rate {2400 | 4800 | 7200 | transmission speed of a fax to be sent to
9600 | 12000 | 14400 | this dial peer. The keyword disable turns
disable | voice} off fax transmission capability. The keyword
voice, which is on by default, specifies the
highest possible transmission speed
supported by the voice rate.
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Table 9.4 Optional Commands for the Configuration of VoIP
Command Description
Continued
AVVID Dial Plans • Chapter 9 289
Gatekeeper(config-dial-peer)# (Optional) This command indicates the
numbering-type {abbreviated | numbering type to match, as defined by
international | national | the ITU Q.931 specification.
network | reserved |
subscriber | unknown}
Gatekeeper(config-dial-peer)# (Optional) This command indicates the type
playout-delay mode of jitter buffer playout delay to use.
{adaptive | fixed}
Gatekeeper(config-dial-peer)# (Optional) This command indicates the
playout-delay {maximum amount of time a packet will be held in the
value | nominal value | jitter buffer before it is played out on the
minimum {default | low | audio path.
high}}
Gatekeeper(config-dial-peer)# (Optional) This command configures the
preference value preference for the VoIP dial peer.
The value is a number from 0 through 10.
The lower the number, the higher the
preference.
Gatekeeper(config-dial-peer)# (Optional) This command indicates a
tech-prefix number particular technology prefix that will be
prepended to the destination-pattern of
this dial peer.
Gatekeeper(config-dial-peer)# (Optional) This command indicates the
translate-outgoing {called | translation rule set that needs to be
calling} name-tag applied to the calling-number or
called-number.
Gatekeeper(config-dial-peer)# (Optional) This command enables voice
vad activity detection (VAD). This will disable
the transmission of packets during periods
of silence. VAD is on by default.
The minimum time of silence detection for
VAD can be configured by using the voice
vad-time global configuration command.
The music threshold can be configured by
using the music-threshold voice-port
command, if you feel it is affecting VAD
performance.