Media5 Mediatrix 4104, Справочное руководство

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SIP Interop Reference Manual (SIP Version)
Mediatrix 4104 65
SIP Publication
You can refresh the publication, i.e., commit the changes you have done to the publication. When refreshing
the publications, all enabled endpoints unpublish themselves from the previous Presence Compositor and
send a new publication to the current Presence Compositor with the current parameters.
You can also set this parameter via SNMP, as described in “Publication Parameters” on page 267 .

To refresh the publications:
1. In the SIP Publication section of the SIP page, set the publication command in the SIP Publication
Command menu.
Figure 30: SIP – SIP Publication section
The following values are available:
• noOp: No operation.
• refresh: Refresh publications.
SIP Interop
The Interop sub-page of the SIP page allows you to configure the SIP penalty box, SIP transport parameters,
and specific interop parameters of the Mediatrix 4104.
SIP Penalty Box
The penalty box feature is used to “quarantine” a given host which address times out. During that time, the
address is considered as “non-responding” for all requests.
This feature is most useful when using multiple servers and some of them are down. It ensures that users wait
a minimal period of time before trying a secondary host.
You can also set these parameters via SNMP, as described in “SIP Penalty Box” on page 265 .
Penalty Box vs Transport Types
Media5 recommends to use this feature with care when supporting multiple transports (see “SIP Transport
Type” on page 67 for more details) or you may experience unwanted behaviours.
When the Mediatrix 4104 must send a packet, it retrieves the destination from the packet. If the destination
address does not specify a transport to use and does not have a DNS SRV entry that configures which
transport to use, then the Mediatrix 4104 tries all transports it supports, starting with UDP. If this fails, it tries
with TCP. The unit begins with UDP because all SIP implementations must support this transport, while the
mandatory support of TCP was only introduced in RFC 3261.
Let’s say for instance that the Mediatrix 4104 supports both the UDP and TCP transports. It tries to reach
endpoint “B” for which the destination address does not specify a transport and there is no DNS SRV entry to
specify which transports to use in which order. It turns out that this endpoint “B” is also down. In this case, the
Mediatrix 4104 first tries to contact endpoint “B” via UDP. After a timeout period, UDP is placed in the penalty
box and the unit then tries to contact endpoint “B” via TCP. This fails as well and TCP is also placed in the
penalty box.
1
Note:
An important fact is that it is not the destination itself that is placed in the penalty box, but the
combination of address, port and transport. When a host is in the penalty box, it is never used to try to
connect to a remote host unless it is the last choice for the Mediatrix 4104 and there are no more options to
try after this host.