Cisco Cisco Expressway
The number of ports used is one of the reasons why the default maximum number of RDP transcode sessions is set to
20, and why the hard limit for maximum Lync B2BUA calls is 100.
20, and why the hard limit for maximum Lync B2BUA calls is 100.
For example, if the B2BUA is handling 100 internal Lync AV calls, and 20 of those calls are doing RDP:
(80*8) + (20*18) + (0*2)= 1000 ports are required, and no further sharing sessions can be accommodated by the
default port range.
default port range.
(In this example, there are no connections to TURN servers)
If you increase the maximum number of RDP transcode sessions, you should also increase the B2BUA media
port range.
port range.
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Cisco Expressway with Microsoft Lync Deployment Guide
Port Reference