<?xml version="1.0"?>
<!DOCTYPE rfc SYSTEM "rfc2629.dtd">

    <!ENTITY rfc2119 PUBLIC ''
      'http://xml.resource.org/public/rfc/bibxml/reference.RFC.2119.xml'>
    <!ENTITY rfc3315 PUBLIC ''
      'http://xml.resource.org/public/rfc/bibxml/reference.RFC.3315.xml'>

<?rfc toc="no" ?>
<?rfc compact="yes" ?>
<?rfc iprnotified="yes" ?>

<rfc category="std" ipr="full3978"
        docName="draft-ietf-dhc-dhcpv6-reconfigure-rebind-02.txt" category="info"
>

    <front>
        <title abbrev="DHCPv6 Reconfigure with Rebind">
        Rebind Capability in DHCPv6 Reconfigure Messages
        </title>

    <author initials="D. R"
      surname="Evans"
      fullname="D. R. Evans">
      <organization>ARRIS International, Inc.</organization>
      <address>
        <postal>
	  <street>7912 Fairview Road</street>
          <city>Boulder</city>
	  <region>CO</region>
          <country>USA</country>
	  <code>80303</code>
        </postal>
        <phone>+1 303.494.0394</phone>
        <email>N7DR@arrisi.com</email>
      </address>
    </author>

    <author initials="R."
      surname="Droms"
      fullname="Ralph Droms">
      <organization>Cisco Systems, Inc.</organization>
      <address>
        <postal>
	  <street>1414 Massachusetts Avenue</street>
          <city>Boxborough</city>
	  <region>MA</region>
          <country>USA</country>
	  <code>01719</code>
        </postal>
        <phone>+1 978.936.1674</phone>
        <email>rdroms@cisco.com</email>
      </address>
    </author>

    <date month="November" year="2007"/>

    <abstract>
    
      <t>This document updates RFC 3315 to allow the Rebind message
      type to appear in the Reconfigure Message option of a
      Reconfigure message, which allows DHCPv6 servers to instruct
      clients to perform a Rebind operation as well as a Renew
      operation.
      </t>

    </abstract>
  </front>

<?rfc needLines="5" ?>

  <middle>
    <section title="Introduction">

      <t><xref target='RFC3315'>DHCPv6</xref> allows a server to send
      an unsolicited Reconfigure message to a client. The client's
      response to a Reconfigure message, according to <xref
      target='RFC3315'></xref> is either a Renew or an
      Information-Request message, depending on the contents of the
      msg-type field in the Reconfigure Message option of the
      Reconfigure message.</t>

      <t>In a network with multiple DHCPv6 servers, the Reconfigure
      message may not be sent by the same server as the one from which
      the client last obtained configuration and/or addressing
      information. If the Reconfigure message commands the client to
      perform a Renew, <xref target='RFC3315'></xref> does not
      specify to which server the client should send the Renew. This
      difficulty is avoided if the server commands the client to
      perform an Information-Request, since such messages are
      multicast. However, Information-Request messages do not cause
      addressing configuration to be returned.</t>

      <t>This document expands the allowed values of the msg-type field 
      to allow the server to indicate that the client is to attempt
      to perform a Rebind; since Rebind messages are multicast, this
      avoids the necessity of the client contacting a particular
      server. Rebind messages also cause all configuration
      information, including addresses, to be returned from a server. </t>

      <t>This document updates section 19 of RFC 3315.</t>
    </section>

    <section title="Terminology">

      <t> The key words MUST, MUST NOT, REQUIRED, SHALL, SHALL NOT,
      SHOULD, SHOULD NOT, RECOMMENDED, MAY, and OPTIONAL in this
      document are to be interpreted as described in <xref
      target='RFC2119'></xref>.
      </t>
    </section>

    <section title="The Reconfigure Message option of the DHCPv6
      Reconfigure Message">

    <t>A server includes a Reconfigure Message option in a Reconfigure
     message to indicate to the client whether the client responds with a
     Renew, an Information-request, or a Rebind message.</t>

   <vspace blankLines='7' />

   <t>The format of this option is:

<figure>
<artwork><![CDATA[
     0                   1                   2                   3
     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |      OPTION_RECONF_MSG        |         option-len            |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |    msg-type   |
    +-+-+-+-+-+-+-+-+
]]></artwork>
</figure></t>

<list style='hanging' hangIndent='20'>
      <t hangText='option-code'>OPTION_RECONF_MSG (19).</t>
      <t hangText='option-len'>1.</t>
      <t hangText='msg-type'>5 for Renew message, 6 for Rebind, 11 for
                             Information-request message.</t>
</list>

      </section>

      <section title="Security Considerations">

      <t>This document adds no new security considerations beyond
      those present in <xref target='RFC3315'></xref>.</t>

      </section>

      <section title="IANA Considerations">

      <t>There are no actions for IANA associated with this document.</t>

      </section>


  </middle>

  <back>
    <references title="Normative References">

      &rfc2119;
      &rfc3315;

    </references>

  </back>
</rfc>
