The administrator can select a method for conveying DTMF and hookflash on a per-line basis. In
addition, the administrator can also configure the MIME type (Content-Type header) used when
conveying DTMF or hookflash in SIP INFO messages. The MIME type is set once for both lines.
DTMF Tx Method Method to transmit DTMF signals to the far end:
Inband = Send DTMF using the audio path; INFO =
Use the SIP INFO method, AVT = Send DTMF as
AVT events; Auto = Use Inband or AVT based on
outcome of codec negotiation
Choice:
{InBand,
AVT,
INFO
Auto}
Auto
Hook Flash Tx Method Select the method to signal Hook Flash events:
• None: do not signal hook flash events
• AVT: use RFC2833 AVT (event=16)
• INFO: use SIP INFO method with the single line
“signal = hf” in the message body. The MIME type for
this message body is taken from the <Hook Flash
MIME Type> paramter
Choice:
{None,
AVT,
INFO}
None
DTMF Relay MIME
Type This is the MIME Type to be used in a SIP
INFO message used to signal DTMF event. Str31 application/dtmf-relay
Hook Flash MIME
Type This is the MIME Type to be used in a SIP
INFO message used to signal hook flash
event.
Str31 application/hook-flash
4.6.2. Codec and Audio Settings
The following parameters are used to enable or disable access to specific codecs, echo cancellation,
and FAX support.
Parameter Name Description Type Default
Preferred Codec Select a preferred codec for all calls. However, the
actual codec used in a call still depends on the
outcome of the codec negotiation protocol.G711u,
G711a, G726-16, G726-24, G726-32, G726-40,
G729a, G723
Choice G711u
Use Pref Codec Only Only use the preferred codec for all calls. The call will
fail if the far end does not support this codec. Bool No
Silence Supp Enable Enable silence suppression so that silent audio
frames are not transmitted Bool No
Echo Canc Enable Enable the use of echo canceller Bool Yes
Echo Canc Adapt
Enable Enable echo canceller to adapt Bool Yes
Echo Supp Enable Enable the use of echo suppressor. If <Echo Canc
Enable> is “no”, this parameter is ignored Bool Yes
G729a Enable1Enable the use of G729a codec at 8 kbps. Bool Yes
G723 Enable1Enable the use of G723 codec at 6.3 kbps Bool Yes
G726-16 Enable1Enable the use of G726 codec at 16 kbps Bool Yes
G726-24 Enable1Enable the use of G726 codec at 24 kbps Bool Yes
G726-32 Enable1Enable the use of G726 codec at 32 kbps Bool Yes
G726-40 Enable1Enable the use of G726 codec at 40 kbps Bool Yes
FAX Passthru Enable *** This parameter has been removed. *** Bool Yes
© 2004 Linksys Proprietary (See Copyright Notice on Page 2)
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