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To support Audio and Video in both directions through the firewall, all UDP ports between 5004 and 65535 must be opened to allow signaling (SIP) and media streams (RTP) to traverse the firewall. This is required because dynamic ports are used. Audio Stream and WB also use dynamic ports for signaling.
File Transfer can be enabled by opening ports 6891 to 6900 on the firewall. Remote Assistance can be enabled by opening port 3389.
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