Network Working Group D. New Request for Comments: 3620 October 2003 Category: Standards Track The TUNNEL Profile Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (2003). All Rights Reserved. Abstract This memo describes a Blocks Extensible Exchange Protocol (BEEP) profile that allows a BEEP peer to serve as an application-layer proxy. It allows authorized users to access services through a firewall. Table of Contents 1. Rationale . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1 One-Hop Example. . . . . . . . . . . . . . . . . . . . . . 3 2.2 Two-Hop Example. . . . . . . . . . . . . . . . . . . . . . 4 2.3 Failed Set-Up Example. . . . . . . . . . . . . . . . . . . 5 2.4 Non-BEEP Example . . . . . . . . . . . . . . . . . . . . . 5 2.5 Profile Example. . . . . . . . . . . . . . . . . . . . . . 6 2.6 Endpoint Example . . . . . . . . . . . . . . . . . . . . . 8 3. Message Syntax. . . . . . . . . . . . . . . . . . . . . . . . 9 4. Message Semantics . . . . . . . . . . . . . . . . . . . . . . 10 5. Provisioning . . . . . . . . . . . . . . . . . . . . . . . . . 12 6. Reply Codes. . . . . . . . . . . . . . . . . . . . . . . . . . 13 7. Security Considerations. . . . . . . . . . . . . . . . . . . . 14 8. Normative References . . . . . . . . . . . . . . . . . . . . . 15 A. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 A.1 Registration: BEEP Profile . . . . . . . . . . . . . . . . 16 A.2 Registration: A System (Well-Known) TCP port number for TUNNEL . . . . . . . . . . . . . . . . . . 16 B. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 17 Author's Address . . . . . . . . . . . . . . . . . . . . . . . 17 Full Copyright Statement . . . . . . . . . . . . . . . . . . . 18 New Standards Track