NAT Behavior Discovery Using Session Traversal Utilities for NAT (STUN)
RFC 5780
Document | Type |
RFC - Experimental
(May 2010; Errata)
Updated by RFC 8553
|
|
---|---|---|---|
Authors | Derek MacDonald , Bruce Lowekamp | ||
Last updated | 2020-01-21 | ||
Replaces | draft-macdonald-behave-nat-behavior-discovery | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized with errata bibtex | ||
Reviews | |||
Stream | WG state | WG Document | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 5780 (Experimental) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | Magnus Westerlund | ||
Send notices to | (None) |
Internet Engineering Task Force (IETF) D. MacDonald Request for Comments: 5780 B. Lowekamp Category: Experimental Skype ISSN: 2070-1721 May 2010 NAT Behavior Discovery Using Session Traversal Utilities for NAT (STUN) Abstract This specification defines an experimental usage of the Session Traversal Utilities for NAT (STUN) Protocol that discovers the presence and current behavior of NATs and firewalls between the STUN client and the STUN server. Status of This Memo This document is not an Internet Standards Track specification; it is published for examination, experimental implementation, and evaluation. This document defines an Experimental Protocol for the Internet community. 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). Not all documents approved by the IESG are a candidate for any level of Internet Standard; see Section 2 of RFC 5741. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc5780. MacDonald & Lowekamp Experimental [Page 1] RFC 5780 NAT Behavior Discovery May 2010 Copyright Notice Copyright (c) 2010 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 (http://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. This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other than English. MacDonald & Lowekamp Experimental [Page 2] RFC 5780 NAT Behavior Discovery May 2010 Table of Contents 1. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 5 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 6 2.1. Example Diagnostic Use . . . . . . . . . . . . . . . . . . 6 2.2. Example Use with P2P Overlays . . . . . . . . . . . . . . 7 2.3. Experimental Goals . . . . . . . . . . . . . . . . . . . . 8 3. Overview of Operations . . . . . . . . . . . . . . . . . . . . 9 3.1. Determining NAT Mapping . . . . . . . . . . . . . . . . . 10 3.2. Determining NAT Filtering . . . . . . . . . . . . . . . . 10 3.3. Binding Lifetime Discovery . . . . . . . . . . . . . . . . 10 3.4. Diagnosing NAT Hairpinning . . . . . . . . . . . . . . . . 11 3.5. Determining Fragment Handling . . . . . . . . . . . . . . 11 3.6. Detecting a Generic Application Level Gateway (ALG) . . . 11 4. Discovery Process . . . . . . . . . . . . . . . . . . . . . . 11 4.1. Source Port Selection . . . . . . . . . . . . . . . . . . 12 4.2. Checking for UDP Connectivity with the STUN Server . . . . 13 4.3. Determining NAT Mapping Behavior . . . . . . . . . . . . . 14 4.4. Determining NAT Filtering Behavior . . . . . . . . . . . . 14 4.5. Combining and Ordering Tests . . . . . . . . . . . . . . . 15 4.6. Binding Lifetime Discovery . . . . . . . . . . . . . . . . 15 5. Client Behavior . . . . . . . . . . . . . . . . . . . . . . . 17 5.1. Discovery . . . . . . . . . . . . . . . . . . . . . . . . 17 5.2. Security . . . . . . . . . . . . . . . . . . . . . . . . . 18 6. Server Behavior . . . . . . . . . . . . . . . . . . . . . . . 18 6.1. Preparing the Response . . . . . . . . . . . . . . . . . . 18Show full document text