Configuring sip session refresh, Introduction to sip session refresh, Configuring compatibility – H3C Technologies H3C MSR 50 User Manual
Page 680
295
Configuring SIP session refresh
Introduction to SIP session refresh
In a high-volume traffic environment, if a BYE message gets lost for a session, the call proxy server will not
know that the session has ended. Therefore, it still maintains the state information for the call, which
wastes resources of the server. To solve this problem, the RFC 4082 defines a session timer mechanism
for SIP sessions: the UA sends periodic re-INVITE or UPDATE requests (called session refresh requests) to
notify the proxy server about the current state of the session. The interval for sending session refresh
requests is determined through the negotiation of both sides.
Two new header fields are added to the session refresh requests:
•
Session-Expires—Conveys the maximum session duration, that is, if no refresh request is received
during this time, the session is considered ended.
•
Min-SE—Conveys the minimum session duration, which is used to avoid frequent refresh requests
from occupying network bandwidth.
Configuring SIP session refresh
Select Voice Management > Call Connection > SIP Connection from the navigation tree, and click the
Session Properties tab to access the SIP session refresh configuration page, as shown in
.
Figure 682 SIP session refresh configuration page
Table 249 Configuration items
Item Description
SIP Session Refresh
•
Enable—Enable SIP session refresh.
•
Disable—Disable SIP session refresh.
You can configure Session Expiration and Min Session Refresh Interval only after
the SIP session refresh function is enabled.
Session Expiration
Maximum and minimum session durations of SIP sessions.
By default,
•
The periodic refresh of SIP sessions is not enabled automatically. That is, if
periodic refresh of SIP sessions is disabled on the called party but enabled on
the calling party, the called party will enable periodic refresh of SIP sessions
after negotiation.
•
The minimum session duration is 90 seconds.
Min Session Refresh
Interval
Configuring compatibility
Select Voice Management > Call Connection > SIP Connection from the navigation tree, and click the
Session Properties tab to access the compatibility configuration page as shown in
.