Medias Mediatrix 1204, Справочное руководство

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Chapter 18 - SIP Protocol Features Session Timers
220 Mediatrix 1204
SIP User Agent Header
The User-Agent header field contains information about the user agent client originating the request. For
instance, the information of the User-Agent header could be something like the following:
User-Agent: Softphone Beta1.5
You can specify if the Mediatrix 1204 sends this information or not when establishing a communication.
X
To enable sending the SIP User Agent header:
1. In the sipInteropMIB , set the sipInteropSendUAHeaderEnable variable to enable .
Session Timers
The session timer extension allows to detect the premature end of a call caused by a network problem or a
peer’s failure by resending an INVITE at every
n seconds.
A successful response (200 OK) to this INVITE indicates that the peer is still alive and reachable. A timeout
to this INVITE may mean that there are problems in the signalling path or that the peer is not available
anymore. In that case, the call is shut down by using normal SIP means.
X
To set Session Timer information:
1. In the sipUAGroupConfigTable group, set the session timer maximum expiration delay in the
sipUAGroupMaximumSessionExpirationDelay variable.
This is the suggested maximum time, in seconds, for the periodical session refreshes. It must be
equal to or greater than the minimum value. This value is reflected in the
Session-Expires header.
2. Set the session timer minimum expiration delay in the
sipUAGroupMinimumSessionExpirationDelay variable.
This is the minimum value, in seconds, for the periodical session refreshes. It must be equal to or
smaller than the maximum value. This value is reflected in the
Min-SE header.
The Min-SE value is a threshold under which proxies and user agents on the signalling path are not
allowed to go.
X
To disable the Session Timer service:
1. Set the sipUAGroupMaximumSessionExpirationDelay variable to 0 .
Increasing the maximum helps to reduce network traffic, but also makes “dead” calls longer to
detect.
Standards Supported RFC 3261 – SIP: Session Initiation Protocol, section 20.41 (User-Agent)