Cisco SPA1112 Provisioning Manual page 107

Voice Parameters
<DTMF_Tx_Method_1_>
through <DTMF_Tx_Method_13_>
<FAX_Disable_ECAN_1_> through
<FAX_Disable_ECAN_2_>
<DTMF_Tx_Mode_1_>
<DTMF_Tx_Mode_2_>
<DTMF_Tx_Mode_5_> through <DTMF_
Tx_Mode_13_>
<DTMF_Tx_Strict_Hold_Off_Time_1_>
<DTMF_Tx_Strict_Hold_Off_Time_2_>
<FAX_Enable_T38_1_>
<FAX_Enable_T38_2_>
Provisioning Guide for Cisco SPA100 and SPA200 Series Analog Telephone Adapters
Select the method to transmit DTMF signals to the far end:
InBand, AVT, INFO, or Auto. InBand sends DTMF by using the
audio path. AVT sends DTMF as AVT events. INFO uses the
SIP INFO method. Auto uses InBand or AVT based on the
outcome of codec negotiation.
Default setting: Auto
If enabled, this feature automatically disables the echo
canceller when a fax tone is detected. To use this feature,
select yes. Otherwise, select no.
Default setting: no
DTMF Detection Tx Mode is available for SIP information and
AVT. Options are: Strict or Normal.
Default setting: Strict for which the following are true:
• A DTMF digit requires an extra hold time after
detection.
• The DTMF level threshold is raised to -20 dBm.
The minimum and maximum duration thresholds are:
• strict mode for AVT: 70 ms
• normal mode for AVT: 40 ms
• strict mode for SIP info: 90 ms
• normal mode for SIP info: 50 ms
This parameter is in effect only when DTMF Tx Mode is set to
strict, and when DTMF Tx Method is set to out-ofband; i.e.
either AVT or SIP-INFO. The value can be set as low as 40 ms.
There is no maximum limit. A larger value will reduce the
chance of talk-off (beeping) during conversation, at the
expense of reduced performance of DTMF detection, which is
needed for interactive voice response systems (IVR) Default:
70 ms
To enable the use of ITU-T T.38 standard for FAX Relay, select
yes. Otherwise select no.
Default setting: yes
6
107