IPv6 Router Advertisement Guard
RFC 6105

Internet Engineering Task Force (IETF)                  E. Levy-Abegnoli
Request for Comments: 6105                               G. Van de Velde
Category: Informational                                    Cisco Systems
ISSN: 2070-1721                                             C. Popoviciu
                                                              Technodyne
                                                              J. Mohacsi
                                                          NIIF/Hungarnet
                                                           February 2011

                    IPv6 Router Advertisement Guard

Abstract

   Routed protocols are often susceptible to spoof attacks.  The
   canonical solution for IPv6 is Secure Neighbor Discovery (SEND), a
   solution that is non-trivial to deploy.  This document proposes a
   light-weight alternative and complement to SEND based on filtering in
   the layer-2 network fabric, using a variety of filtering criteria,
   including, for example, SEND status.

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/rfc6105.

Levy-Abegnoli, et al.         Informational                     [Page 1]
RFC 6105                      IPv6 RA-Guard                February 2011

Copyright Notice

   Copyright (c) 2011 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
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   publication of this document.  Please review these documents
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   include Simplified BSD License text as described in Section 4.e of
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   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.

Table of Contents

   1. Introduction ....................................................3
   2. Model and Applicability .........................................3
   3. Stateless RA-Guard ..............................................5
   4. Stateful RA-Guard ...............................................6
      4.1. State Machine ..............................................6
      4.2. SEND-Based RA-Guard ........................................8
   5. RA-Guard Use Considerations .....................................8
   6. Security Considerations .........................................9
   7. Acknowledgements ................................................9
   8. References ......................................................9
      8.1. Normative References .......................................9
      8.2. Informative References .....................................9

Levy-Abegnoli, et al.         Informational                     [Page 2]
RFC 6105                      IPv6 RA-Guard                February 2011

1.  Introduction

   When operating IPv6 in a shared layer-2 (L2) network segment without
   complete SEcure Neighbor Discovery (SEND) support by all devices
   connected or without the availability of the infrastructure necessary
   to support SEND [RFC3971], there is always the risk of facing
   operational problems due to rogue Router Advertisements (RAs)
   generated maliciously or unintentionally by unauthorized or
   improperly configured routers connecting to the segment.