Configure Modem Tone Detection

You configure modem tone detection in the config-policy to enable the SBC to detect modem tones during transcoded calls, and switch calls to modem calls.

This procedure highlights the relevant parameters for enabling modem tone detection, and not necessarily all required parameters. When a call is being transcoded, modem tones are only detected if all three configurations mentioned below are set. If any one is missing, modem tones are ignored.
  1. Access the codec-policy configuration element. 
    ORACLE# configure terminal
ORACLE(configure)# media-manager
ORACLE(media-manager)# codec-policy
ORACLE(codec-policy)# select
  2. Select the codec-policy object to edit. 
    ORACLE(codec-policy)# select
<name>:
1:  name=cp1
2:  name=cp2

selection: 2
ORACLE(codec-policy)#
  3. add-codecs-on-egress: Include either G711AOMD or G711UOMD, or both, depending on the value the m= line should have on the reINVITE.
    When you include the codecs in add-codecs-on-egress, the VBD tones will be transmitted, even if you do not allow g711a or g711u in allow-codecs (either by setting them to :no, or simply not including them.)
  4. tone-detection: Include either modem-orig or modem-ans, depending on the direction you want to accept modem tones from. You cannot include both in the same codec-policy.
    You can enable these alongside the fax-cng and fax-v21 options for fax detection.
  5. tone-detection-xcode-only: Enable this parameter.
  6. Type done to save your configuration.