TURN Server - Definition, History and Explanation

A TURN (Traversal Using Relays around NAT) server is a network entity that facilitates communication between two devices or clients located behind Network Address Translation (NAT) systems or firewalls. It acts as a relay for network traffic, allowing devices to communicate with each other when direct connections are not possible due to NAT or firewall restrictions. TURN servers come into play when STUN (Session Traversal Utilities for NAT) fails and ensures data delivery through relaying but introduces added latency. Developers typically use a combination of STUN and TURN in their applications, with TURN serving as a reliable fallback for scenarios where direct communication is blocked.