One document matched: draft-ietf-idr-as0-00.xml

<?xml version="1.0" encoding="US-ASCII"?>
<!DOCTYPE rfc SYSTEM "rfc2629.dtd">
<!-- WK: Set category, IPR, docName -->
<rfc category="std" docName="draft-ietf-idr-as0-00" ipr="trust200902">
  <?xml-stylesheet type='text/xsl' href='rfc2629.xslt' ?>

  <?rfc toc="yes" ?>

  <?rfc symrefs="yes" ?>

  <?rfc sortrefs="yes"?>

  <?rfc iprnotified="no" ?>

  <?rfc strict="yes"?>

  <?rfc compact="yes" ?>

  <front>
    <!-- WK: Set long title. -->

    <title abbrev="as0-processing">Codification of AS 0 processing.</title>

    <author fullname="Warren Kumari" initials="W." surname="Kumari">
      <organization>Google</organization>

      <address>
        <postal>
          <street>1600 Amphitheatre Parkway</street>

          <city>Mountain View, CA</city>

          <code>94043</code>

          <country>US</country>
        </postal>

        <email>warren@kumari.net</email>
      </address>
    </author>

    <author fullname="Randy Bush" initials="R." surname="Bush">
      <organization>Internet Initiative Japan</organization>

      <address>
        <postal>
          <street>5147 Crystal Springs</street>

          <city>Bainbridge Island, WA</city>

          <code>98110</code>

          <country>US</country>
        </postal>

        <email>randy@psg.com</email>
      </address>
    </author>

    <author fullname="Heather Schiller" initials="H." surname="Schiller">
      <organization>Verizon</organization>

      <address>
        <postal>
          <street>22001 Loudoun County Parkway</street>

          <city>Ashburn</city>

          <code>20147</code>

          <country>US</country>
        </postal>

        <email>heather.schiller@verizon.com</email>
      </address>
    </author>

    <date day="29" month="November" year="2011" />

    <area>int</area>

    <workgroup>idr</workgroup>

    <abstract>
      <t>This document proscribes the use of AS 0 in BGP OPEN and AS_PATH /
      AS4_PATH BGP attribute.</t>
    </abstract>
  </front>

  <middle>
    <section title="Introduction">
      <t>Autonomous System 0 is listed in the IANA Autonomous System Number
      Registry as "Reserved - May be use to identify non-routed networks"
      (<xref target="IANA.AS_Numbers"></xref>).</t>

      <t><xref target="I-D.ietf-sidr-iana-objects"></xref> specifies that AS
      number zero in a ROA is used to mark an NLRI which is to be marked as
      Invalid.</t>

      <t>No clear statement that AS 0 was proscribed could be found in any BGP
      specification.</t>

      <t>As at least two implementations discard routes containing AS 0 (and
      to allow approaches such as the above) this document codifies this
      behavior.</t>

      <section title="Requirements notation">
        <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>

    <section title="Behavior">
      <t>This document specifies that a BGP speaker MUST NOT originate or
      propagate a route with an AS number of zero. If a BGP speaker receives a
      route which has an AS number of zero in the AS_PATH (or AS4_PATH)
      attribute, it SHOULD be logged and treated as a WITHDRAW. This same
      behavior applies to routes containing zero as the Aggregator or AS4
      Aggregator.</t>

      <t>In addition if a BGP speaker receives zero as the peer AS in an OPEN
      message, it MUST abort the connection and send a NOTIFICATION with Error
      Code "OPEN Message Error" and subcode "Bad Peer AS" (see <xref
      target="RFC4271"></xref> Section 6.2). Obviously enough, a router MUST
      NOT initiate a connection claiming to be AS number zero.</t>
    </section>

    <section title="IANA Considerations">
      <t>The IANA is requested to update the Reference for number 0 in the
      "Autonomous System (AS) Numbers" registry to reference this
      document.</t>
    </section>

    <section anchor="security" title="Security Considerations">
      <t>By allowing resource holders to say that AS 0 is the only valid
      origin for a route, we allow them to state that a particular address
      resource is not in use. By ensuring that all implementations that see AS
      0 in a route ignore that route, we prevent a malicious party from
      announcing routes containing AS 0 in an attempt to hijack those
      resources.</t>

      <t>In addition, by standardizing the behavior upon reception of an
      AS_PATH (or AS4_PATH) containing AS 0, this document makes the behavior
      better defined, and security gotchas often lurk in the undefined
      spaces.</t>
    </section>

    <section title="Acknowledgements">
      <t>The authors wish to thank Enke Chen, Robert Raszuk, Danny McPherson,
      Keyur Patel, John Scudder. Apologies to those we may have missed, it was
      not intentional.</t>
    </section>
  </middle>

  <back>
    <references title="Normative References">
      <?rfc include='reference.RFC.2119.xml'?>

      <?rfc include='reference.RFC.4271.xml'?>

      <reference anchor="IANA.AS_Numbers"
                 target="http://www.iana.org/assignments/as-numbers">
        <front>
          <title abbrev="Autonomous System (AS) Numbers">Autonomous System
          (AS) Numbers</title>

          <author>
            <organization>IANA</organization>
          </author>

          <date />
        </front>
      </reference>
    </references>

    <references title="Informative References">
      <?rfc include='reference.I-D.draft-ietf-sidr-iana-objects-03.xml'?>
    </references>

    <section title="Changes / Author Notes.">
      <t>[RFC Editor: Please remove this section before publication ]</t>

      <t>Draft accepted as IDR Doc, notes reset. Please see notes for
      draft-wkumari-idr-as0.xml for prior comments.</t>

      <t>Changes -00.</t>

      <t><list style="symbols">
          <t>Added AS4_PATH -- Robert Raszuk.</t>

          <t>Change "bgp listener" to "bgp speaker" -- Enke Chen</t>

          <t>Consistent use of AS_PATH (v., AS-PATH and AS PATH) -- Danny
          McPherson</t>

          <t>New text for Sec 2 P1 -- Enke / Keyur / Scudder,
          http://www.ietf.org/mail-archive/web/idr/current/msg05786.html</t>

          <t>I made a boo boo -- I had the file open in 2 editors, made
          changes in one and overwrote them by saving on the other, then
          checked the broken one into SVN. Apologies to all whose comments I
          may have missed...</t>
        </list></t>
    </section>
  </back>
</rfc>