Administration
A31003-S2000-M102-3-76A9, 08/07/2009
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Asterisk - OpenStage Family, Administration Manual
administration.fm
System Settings
3.4.8
SIP Session Timer
Session timers provide a basic keep-alive mechanism between 2 user agents or phones. This
mechanism can be useful to the endpoints concerned or for stateful proxies to determine that
a session is still alive. This is achieved by the phone sending periodic re-INVITEs to keep the
session alive. If no re-INVITE is received before the interval passes, the session is considered
terminated. Both phones are supposed to terminate the call, and stateful proxies can remove
any state for the call.
This feature is sufficiently backward compatible such that only one end of a call needs to im-
plement the SIP extension for it to work.
The parameter
Session timer enabled
determines whether the mechanism shall be used, and
Session duration (seconds)
sets the expiration time, and thus the interval between refresh
re-INVITEs.
Data required
•
Session timer enabled
: Activates or deactivates the session timer mechanism.
Value range: "Yes", "No".
Default value: "No".
•
Session duration (seconds)
: Sets the expiration time for a SIP session.
Default: 3600.
>
Some server environments support their own mechanism for auditing the health of
a session. In these cases, the
Session timer
must be deactivated.