Session Traversal Utilities for NAT (STUN)
RFC 8489
Document | Type |
RFC - Proposed Standard
(February 2020; Errata)
Obsoletes RFC 5389
|
|
---|---|---|---|
Authors | Marc Petit-Huguenin , Gonzalo Salgueiro , Jonathan Rosenberg , Dan Wing , Rohan Mahy , Philip Matthews | ||
Last updated | 2020-09-16 | ||
Stream | Internent Engineering Task Force (IETF) | ||
Formats | plain text html pdf htmlized (tools) htmlized with errata bibtex | ||
Reviews | |||
Stream | WG state | Submitted to IESG for Publication | |
Document shepherd | Tolga Asveren | ||
Shepherd write-up | Show (last changed 2018-02-02) | ||
IESG | IESG state | RFC 8489 (Proposed Standard) | |
Action Holders |
(None)
|
||
Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Magnus Westerlund | ||
Send notices to | Tolga Asveren <tasveren@rbbn.com>, Gonzalo.Camarillo@ericsson.com | ||
IANA | IANA review state | Version Changed - Review Needed | |
IANA action state | RFC-Ed-Ack |
Internet Engineering Task Force (IETF) M. Petit-Huguenin Request for Comments: 8489 Impedance Mismatch Obsoletes: 5389 G. Salgueiro Category: Standards Track Cisco ISSN: 2070-1721 J. Rosenberg Five9 D. Wing Citrix R. Mahy Unaffiliated P. Matthews Nokia February 2020 Session Traversal Utilities for NAT (STUN) Abstract Session Traversal Utilities for NAT (STUN) is a protocol that serves as a tool for other protocols in dealing with 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 document obsoletes RFC 5389. Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc8489. Petit-Huguenin, et al. Standards Track [Page 1] RFC 8489 STUN February 2020 Copyright Notice Copyright (c) 2020 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction ....................................................4 2. Overview of Operation ...........................................5 3. Terminology .....................................................7 4. Definitions .....................................................7 5. STUN Message Structure ..........................................9 6. Base Protocol Procedures .......................................11 6.1. Forming a Request or an Indication ........................11 6.2. Sending the Request or Indication .........................12 6.2.1. Sending over UDP or DTLS-over-UDP ..................13 6.2.2. Sending over TCP or TLS-over-TCP ...................14 6.2.3. Sending over TLS-over-TCP or DTLS-over-UDP .........15 6.3. Receiving a STUN Message ..................................16 6.3.1. Processing a Request ...............................17 6.3.1.1. Forming a Success or Error Response .......17 6.3.1.2. Sending the Success or Error Response .....18 6.3.2. Processing an Indication ...........................18 6.3.3. Processing a Success Response ......................19 6.3.4. Processing an Error Response .......................19 7. FINGERPRINT Mechanism ..........................................20 8. DNS Discovery of a Server ......................................20 8.1. STUN URI Scheme Semantics .................................21 9. Authentication and Message-Integrity Mechanisms ................22 9.1. Short-Term Credential Mechanism ...........................23 9.1.1. HMAC Key ...........................................23 9.1.2. Forming a Request or Indication ....................23 9.1.3. Receiving a Request or Indication ..................23Show full document text