Whether STUN server is needed within LAN for WebRTC?

Question

I have developed a p2p video chat using Webrtc. I am aware that STUN or TURN server is required to identify the public IP behind NAT. Currently am using Google's STUN server.

I have the application installed in the server connected to the LAN which will not have internet access, do I need to install the STUN server in my server to make Webrtc video chat work within the LAN?

Answer 1

Peers should be able to connect within a LAN (on the same side of a NAT) without STUN, i.e. using the host candidates. Try it out!

Answer 2

In general, you won't need a STUN server. However, depending on the firewall configuration, you may actually need STUN (and even TURN). For example, at the SFHTML5 WebRTC Hackathon, we were on a corporate guest WiFi network that blocked local UDP and TCP traffic. Making successful calls required a TURN server in this case.