Cisco TelePresence Administrator's Manual page 247

Applications
Field Description
Encryption Controls how the B2BUA handles encrypted
and unencrypted call legs.
Required: both legs of the call must be
encrypted.
Auto: encrypted and unencrypted combinations
are supported.
The default is Auto.
B2BUA media The port range used by the B2BUA for handling
port range media. Default range is 56000–57000.
start/end
Hop count Specifies the Max-Forwards value to use in SIP
messages. Default is 70.
Session refresh The maximum time allowed between session
interval refresh requests for SIP calls. Default is 1800
seconds.
Minimum The minimum value the B2BUA will negotiate for
session refresh the session refresh interval for SIP calls. Default
interval is 500 seconds.
Port on B2BUA The port used on the B2BUA for communicating
for VCS with the VCS. Default is 65070.
communications
Port on B2BUA The port used on the B2BUA for call
for Lync call communications with the Microsoft Lync server.
communications Default is 65072.
Configuring the B2BUA's trusted hosts
The B2BUA trusted hosts
used to specify the devices that may send signaling messages to the Lync B2BUA.
The B2BUA only accepts messages from devices whose IP address is included in the list of trusted hosts.
Note that trusted host verification only applies to calls initiated by Lync that are inbound to the VCS video
network. It is not necessary to configure trusted hosts if calls are only ever to be initiated from the VCS video
network.
The configurable options are:
Field Description
Name An optional free-form description of the trusted
host device.
IP address The IP address of the trusted host device.
Cisco VCS Administrator Guide (X8.1.1)
page (Applications > B2BUA > Microsoft Lync > B2BUA trusted
B2BUA (back-to-back user agent) overview
Usage tips
A call via the B2BUA comprises two legs:
one leg from the B2BUA to a standard
video endpoint, and one leg from the
B2BUA to the Lync client. Either leg of the
call could be encrypted or unencrypted.
A setting of Auto means that the call can
be established for any of the encrypted
and unencrypted call leg combinations.
Thus, one leg of the call could be
encrypted while the other leg could be
unencrypted.
Ensure that the port range does not
overlap with other port ranges used by this
VCS or this VCS's TURN server.
For further information see the definition of
Session-Expires in RFC 4028.
For further information see the definition of
Min-SE header in RFC 4028.
Usage tips
The name is not used as part of the "trusted"
criteria. It is provided only to help
distinguish between multiple devices, rather
than having to rely on their IP addresses.
hosts) is
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