Tech Docs

Firewall ports for Skype for Business / Lync integrations

When integrating Pexip Infinity with Microsoft Skype for Business and Lync*, the following ports have to be allowed through any firewalls which carry traffic for the involved devices:

Direction Purpose Protocol Source Destination
Between the SfB/Lync FEP and the Conferencing Node (bidirectional) SIP signaling TCP <any> 5061
From SfB/Lync clients towards the Conferencing Nodes RTP/RTCP media UDP <any> 40000–49999
From SfB/Lync clients towards the Conferencing Nodes HTTP conference avatar TCP <any> 80
From the Conferencing Nodes towards a SfB/Lync Edge Server (AV Edge Interface) RTP/RTCP/RDP media UDP / TCP 40000–49999 50000–59999
From the SfB/Lync Edge Server (AV Edge Interface) towards Conferencing Nodes RTP/RTCP/RDP media UDP / TCP 50000–59999 40000–49999
From the Conferencing Nodes towards SfB/Lync clients or SfB/Lync servers RTP/RTCP/RDP media UDP / TCP 40000–49999 <any>
From the Conferencing Nodes towards the TURN server RTP/RTCP media UDP 40000–49999 3478
From the Conferencing Nodes towards the SfB/Lync Web Conferencing service PSOM (PowerPoint presentation from SfB/Lync) TCP (TLS) 55000–65535 443 / 8057 †
From the Conferencing Nodes towards the SfB/Lync Front End Server or Edge Server HTTPS (PowerPoint presentation from SfB/Lync) TCP (TLS) 55000–65535 443
† typically 443 for Web Conferencing Edge and 8057 for a SfB/Lync Front End Server / FEP

For a complete list of Pexip Infinity Conferencing Node port usage, see Pexip Infinity port usage and firewall guidance.

* Note that where this documentation refers to "SfB/Lync", it represents both Microsoft Skype for Business and Lync unless stated otherwise.

Skype for Business / Lync clients behind strict firewalls

If your SfB/Lync clients are behind a strict network, and only the minimum ports are allowed for B2B SfB/Lync communication, you may need to allow a few extra flows outbound:

  • Your PC must be able to connect outbound to the internal interface of your SfB/Lync AV Edge Servers on port 3478/UDP (blue arrow).
  • Your SfB/Lync AV Edge servers must be able to connect outbound to Pexip Conferencing Nodes for media, on port range 40000–49999 TCP & UDP for optimal HD video and content sharing (orange arrow).