What are STUN, TURN, and ICE? STUN, TURN, and ICE are a set of IETF standard protocols for negotiating traversing NATs when establishing peer-to-peer communication sessions. WebRTC and other VoIP stacks implement support for ICE to improve the reliability of IP communications. A host uses Session Traversal Utilities for NAT (STUN) to discover its public IP address when it is located behind a NAT/F