AudioCodes Mediant 500 E-SBC, User Manual

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User's Manual 886 Document #: LTRT-10437
Mediant 500 E-SBC
Parameter Description
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.
Web: SBC Session-Expires
CLI: sbc-sess-exp-time
[SBCSessionExpires]
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.
Web: Minimum Session-Expires
CLI: min-session-expires
[SBCMinSE]
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.
Web: SBC Session Refreshing
Policy
CLI: configure voip/sbc general-
setting/sbc-session-refresh-policy
[SBCSessionRefreshingPolicy]
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.
Web: User Registration Grace
Time
CLI: configure voip/sbc general-
setting/sbc-usr-reg-grace-time
[SBCUserRegistrationGraceTime
]
Defines additional time (in seconds) to add to the registration
expiry time of registered users in the device's Users
Registration database.
The valid value is 0 to 300 (i.e., 5 minutes). The default is 0.