Internet Engineering Task Force (IETF) R. Mahy Request for Comments: 5766 Unaffiliated Category: Standards Track P. Matthews ISSN: 2070-1721 Alcatel-Lucent J. Rosenberg jdrosen.net April 2010 Traversal Using Relays around NAT (TURN): Relay Extensions to Session Traversal Utilities for NAT (STUN) Abstract If a host is located behind a NAT, then in certain situations it can be impossible for that ho