If your organization’s firewalls do not support wildcard name configurations, you will have to manually determine the IP address ranges that you would like to allow and the specified ports. For more details, you can refer to:
In addition to the port requirements for internal Lync Server 2013 communication, you must also configure the following ports.
TCP 443, TCP 80 and 443, TCP 5061, PSOM/TLS 443, STUN/TCP 443, STUN/UDP 3478, RTP/TCP 50000-59999
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