Yealink SIP-T54S Administrator's Manual page 759

Parameters
action_url.missed_call
Description:
Configures the action URL the IP phone sends when missing a call.
Example:
action_url.missed_call = http://192.168.0.20/help.xml?IP=$ip
Web User Interface:
Features->Action URL->Missed Call
Phone User Interface:
None
action_url.call_terminated
Description:
Configures the action URL the IP phone sends when terminating a call.
Example:
action_url.call_terminated = http://192.168.0.20/help.xml?IP=$ip
Web User Interface:
Features->Action URL->Terminated
Phone User Interface:
None
action_url.busy_to_idle
Description:
Configures the action URL the IP phone sends when changing the state of the IP phone
from busy to idle.
Example:
action_url.busy_to_idle = http://192.168.0.20/help.xml?IP=$ip
Web User Interface:
Features->Action URL->Busy To Idle
Phone User Interface:
None
action_url.idle_to_busy
Configuring Advanced Features
Permitted Values
URL within 511 characters
URL within 511 characters
URL within 511 characters
URL within 511 characters
Default
Blank
Blank
Blank
Blank
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