Cisco Systems Linksys PAP2, RT31P2 4.6.2. Codec and Audio Settings

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