Triggering DHCPv6 Reconfiguration from Relay Agents
RFC 6977

Internet Engineering Task Force (IETF)                      M. Boucadair
Request for Comments: 6977                                   X. Pougnard
Category: Standards Track                                 France Telecom
ISSN: 2070-1721                                                July 2013

          Triggering DHCPv6 Reconfiguration from Relay Agents

Abstract

   This document defines two new DHCPv6 messages: Reconfigure-Request
   and Reconfigure-Reply.  The Reconfigure-Request message is sent by a
   DHCPv6 relay agent to notify a DHCPv6 server about a configuration
   information change, so that the DHCPv6 server can send a Reconfigure
   message accordingly.  The Reconfigure-Reply message is used by the
   server to acknowledge the receipt of the Reconfigure-Request message.

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 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/rfc6977.

Copyright Notice

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   document authors.  All rights reserved.

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Boucadair & Pougnard         Standards Track                    [Page 1]
RFC 6977         DHCPv6 Relay-Triggered Reconfiguration        July 2013

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Requirements Language . . . . . . . . . . . . . . . . . . . .   3
   3.  Problem Statement . . . . . . . . . . . . . . . . . . . . . .   3
   4.  Solution Overview . . . . . . . . . . . . . . . . . . . . . .   4
   5.  Link Address Option . . . . . . . . . . . . . . . . . . . . .   6
   6.  Detailed Specification  . . . . . . . . . . . . . . . . . . .   6
     6.1.  Messages Format . . . . . . . . . . . . . . . . . . . . .   6
     6.2.  Messages Validation . . . . . . . . . . . . . . . . . . .   7
       6.2.1.  Reconfigure-Request . . . . . . . . . . . . . . . . .   7
       6.2.2.  Reconfigure-Reply . . . . . . . . . . . . . . . . . .   7
     6.3.  Creation and Transmission of a Reconfigure-Request  . . .   7
     6.4.  Intermediate Relay Agents Behavior  . . . . . . . . . . .   9
     6.5.  Server Behavior . . . . . . . . . . . . . . . . . . . . .   9
     6.6.  Receipt of a Reconfigure-Reply  . . . . . . . . . . . . .  10
   7.  Rate-Limiting Considerations  . . . . . . . . . . . . . . . .  10
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  11
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .  11
   10. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  12
   11. References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
     11.1.  Normative References . . . . . . . . . . . . . . . . . .  12
     11.2.  Informative References . . . . . . . . . . . . . . . . .  12

1.  Introduction

   This document specifies two new DHCPv6 messages [RFC3315]:
   Reconfigure-Request and Reconfigure-Reply.

   Section 3 describes a typical problem scenario encountered that
   triggers the DHCPv6 server to issue a Reconfigure message when the
   configuration data is supplied by the relay agent.  This problem may
   be encountered in other contexts.  It is out of scope of this
   document to list all these cases.

   Section 4 describes the proposed solution that relies on the use of
   Reconfigure-Request and Reconfigure-Reply messages.  The Reconfigure-
   Request message is sent by a DHCPv6 relay agent to notify a DHCPv6
   server about a configuration-information change, so that the DHCPv6
   server can send a Reconfigure message accordingly.  The Reconfigure-
   Reply message is used by the server to acknowledge the receipt of
   Reconfigure-Request.

   Section 5 specifies the Link Address Option used by the relay agent
   to indicate the link on which the client is located to the server.

   Section 6 provides the detailed specification of the procedure to