Rogue IPv6 Router Advertisement Problem Statement
RFC 6104

Internet Engineering Task Force (IETF)                          T. Chown
Request for Comments: 6104                     University of Southampton
Category: Informational                                        S. Venaas
ISSN: 2070-1721                                            Cisco Systems
                                                           February 2011

           Rogue IPv6 Router Advertisement Problem Statement

Abstract

   When deploying IPv6, whether IPv6-only or dual-stack, routers are
   configured to send IPv6 Router Advertisements (RAs) to convey
   information to nodes that enable them to autoconfigure on the
   network.  This information includes the implied default router
   address taken from the observed source address of the RA message, as
   well as on-link prefix information.  However, unintended
   misconfigurations by users or administrators, or possibly malicious
   attacks on the network, may lead to bogus RAs being present, which in
   turn can cause operational problems for hosts on the network.  In
   this document, we summarise the scenarios in which rogue RAs may be
   observed and present a list of possible solutions to the problem.  We
   focus on the unintended causes of rogue RAs in the text.  The goal of
   this text is to be Informational, and as such to present a framework
   around which solutions can be proposed and discussed.

Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for informational purposes.

   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/rfc6104.

Chown & Venaas                Informational                     [Page 1]
RFC 6104            Rogue IPv6 Router Advertisements       February 2011

Copyright Notice

   Copyright (c) 2011 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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   it for publication as an RFC or to translate it into languages other
   than English.

Chown & Venaas                Informational                     [Page 2]
RFC 6104            Rogue IPv6 Router Advertisements       February 2011

Table of Contents

   1. Introduction ....................................................4
   2. Bogus RA Scenarios ..............................................4
      2.1. Administrator Misconfiguration .............................5
      2.2. User Misconfiguration ......................................5
      2.3. Malicious Misconfiguration .................................5
   3. Methods to Mitigate against Rogue RAs ...........................6
      3.1. Manual Configuration .......................................6
      3.2. Introducing RA Snooping ....................................6
      3.3. Using ACLs on Managed Switches .............................7
      3.4. SEcure Neighbor Discovery (SEND) ...........................7
      3.5. Router Preference Option ...................................8
      3.6. Relying on Layer 2 Admission Control .......................8
      3.7. Using Host-Based Packet Filters ............................8
      3.8. Using an "Intelligent" Deprecation Tool ....................8