Windows 8.1 and 10 devices which support Miracast and Intel® WiDi do not require ports to be opened in the network firewall. The Intel® WiDi software application for Windows 7 uses varying port numbers for each connection and must be allowed or "whitelisted" in your network firewall. See the article My antivirus software or firewall is preventing me from connecting my PC/laptop to ScreenBeam. What can I do? for more information.