If you are behind a strict network, and you may not access the public Internet on highports typically used for video streams, you may need to allow outbound traffic to the Pexip media ports.
To narrow it down, you can choose to only open this towards the conference nodes you are connecting to. Remember there will normally be more than one conferencing node.
Your PC must be able to connet outbound to Pexip Conferencing nodes for media, on portrange 40.000-49.999 TCP & UDP for optimal HD video and content sharing (orange arrow).
If using WebRTC we also recommend having at least 700 Kbps upstream and downstream for decent quality.