AudioCodes Mediant 800B MSBR User Manual page 986

Parameter
Web: SBC Session-Expires
CLI: sbc-sess-exp-time
[SBCSessionExpires]
Web: Minimum Session-Expires
CLI: min-session-expires
[SBCMinSE]
Web: SBC Session Refreshing
Policy
CLI: configure voip/sbc general-
setting/sbc-session-refresh-policy
[SBCSessionRefreshingPolicy]
Web: User Registration Grace
Time
CLI: configure voip/sbc general-
setting/sbc-usr-reg-grace-time
User's Manual

If the received header's original value is less than this
parameter's value, the header's value is decremented before
being sent on.

If the received header's original value is greater than the
parameter's value, the header's value is replaced by the user-
defined parameter's value.
The valid value range is 1-70. The default is 10.
Defines the SBC session refresh timer (in seconds) in the
Session-Expires header of outgoing INVITE messages.
The valid value range is 90 (according to RFC 4028) to 86400.
The default is 180.
Defines the minimum amount of time (in seconds) between
session refresh requests in a dialog before the session is
considered timed out. This value is conveyed in the SIP Min-SE
header.
The valid range is 0 (default) to 1,000,000, where 0 means that
the device does not limit Session-Expires.
Defines the SIP user agent responsible for periodically sending
refresh requests for established sessions (active calls). The
session refresh allows SIP UAs or proxies to determine the status
of the SIP session. When a session expires, the session is
considered terminated by the UAs, regardless of whether a SIP
BYE was sent by one of the UAs.
The SIP Session-Expires header conveys the lifetime of the
session, which is sent in re-INVITE or UPDATE requests (session
refresh requests). The 'refresher=' parameter in the Session-
Expires header (sent in the initial INVITE or subsequent 2xx
response) indicates who sends the session refresh requests. If
the parameter contains the value 'uac', the device performs the
refreshes; if the parameter contains the value 'uas', the remote
proxy performs the refreshes. An example of the Session-Expires
header is shown below:
Session-Expires: 4000;refresher=uac
Thus, this parameter is useful when a UA does not support
session refresh requests or does not support the indication of
who performs session refresh requests. In such a scenario, the
device can be configured to perform the session refresh requests.

[0] Remote Refresher = (Default) The UA (proxy) performs the
session refresh requests. The device indicates this to the UA
by sending the SIP message with the 'refresher=' parameter in
the Session-Expires header set to 'uas'.

[1] SBC Refresher = The device performs the session refresh
requests. The device indicates this to the UA by sending the
SIP message with the 'refresher=' parameter in the Session-
Expires header set to 'uac'.
Note: The time values of the Session-Expires (session refresh
interval) and Min-SE (minimum session refresh interval) headers
can be configured using the SBCSessionExpires and SBCMinSE
parameters, respectively.
Defines additional time (in seconds) to add to the registration
expiry time of registered users in the device's Users Registration
database.
986
Mediant 800B MSBR
Description
Document #: LTRT-12813