RFC 5389 · PROPOSED STANDARD · 2008

Session Traversal Utilities for NAT

Overview

RFC 5389, “Session Traversal Utilities for NAT”, is a Proposed Standard document published in October 2008 by J. Rosenberg, R. Mahy, P. Matthews, D. Wing. It obsoletes RFC 3489. It has since been updated by RFC 7350, RFC 8553. It has been obsoleted by RFC 8489 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

Session Traversal Utilities for NAT (STUN) is a protocol that serves as a tool for other protocols in dealing with Network Address Translator (NAT) traversal. It can be used by an endpoint to determine the IP address and port allocated to it by a NAT. It can also be used to check connectivity between two endpoints, and as a keep-alive protocol to maintain NAT bindings. STUN works with many existing NATs, and does not require any special behavior from them.

STUN is not a NAT traversal solution by itself. Rather, it is a tool to be used in the context of a NAT traversal solution. This is an important change from the previous version of this specification (RFC 3489), which presented STUN as a complete solution.

This document obsoletes RFC 3489. [STANDARDS-TRACK]

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 5389 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 3489
Obsoleted by
RFC 8489
Updated by
RFC 7350 RFC 8553
Other RFCs from 2008

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