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ripe-679: This document describes the policies for the assignment of globally unique Autonomous System (AS) Numbers within the ripe-072: RIPE NCC service region. These policies are developed by the RIPE Community following the RIPE Policy Development Process. Internet Numbers Registration Procedures
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insert: <b> This documents obsoletes ripe-65, version 0.6 of this document insert: </b> insert: <br />
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Abstract delete: </strong> delete: </h3> delete: <p class="western"> insert: <br />
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This document describes the policies for the assignment of globally unique Autonomous System (AS) Numbers within the RIPE NCC service region. These policies are developed procedures for the reassignment of IP insert: <br />
network numbers from blocks obtained from the RIPE Network Coordination insert: <br />
Centre. It deals with items as providing information for the RIPE insert: <br />
database, as well as reassignment of IP addresses in light of insert: <br />
the "Supernetting" proposal, as documented in RFC 1338, by the RIPE Community following the RIPE Policy Development Process. delete: </p> delete: <p class="western"> delete: </p> delete: <h3> delete: <strong> Contents delete: </strong> delete: </h3> delete: <p class="western"> 1.0 delete: <a class="anchor-link" title="" href="#Definition" target="_self"> Definition delete: <br /> delete: </a> 2.0 delete: <a class="anchor-link" title="" href="#AssignmentCriteria" target="_self"> Assignment Criteria delete: <br /> delete: </a> 3.0 delete: <a class="anchor-link" title="" href="#Returning" target="_self"> Returning AS Numbers delete: <br /> delete: </a> 4.0 delete: <a class="anchor-link" title="" href="#Transferring" target="_self"> Transferring AS Numbers delete: <br /> delete: </a> 5.0 delete: <a class="anchor-link" title="" href="#ASnumbers" target="_self"> 32-bit AS Numbers delete: <br /> delete: </a> 6.0 delete: <a class="anchor-link" title="" href="#Registration" target="_self"> Registration delete: <br /> delete: </a> 7.0 delete: <a class="anchor-link" title="" href="#References" target="_self"> References delete: <br /> delete: </a> 8.0 delete: <a class="anchor-link" title="" href="#Attribution" target="_self"> Attribution delete: </a> delete: </p> delete: <p class="western"> delete: </p> delete: <h3> delete: <a name="Definition"> delete: </a> 1.0 Definition delete: </h3> delete: <p class="western"> An Autonomous System (AS) Vince Fuller insert: <br />
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Introduction insert: <br />
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Since May 1st 1992, the RIPE Network Coordination Centre (NCC) is a group of insert: <br />
acting as a delegated registry for IP networks run numbers to NICs and NOCs insert: <br />
in Europe. It is RIPE NCC policy not to give out network numbers to insert: <br />
individual organisations, who should refer in turn, to their IP network insert: <br />
service provider. insert: <br />
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The mission of the RIPE NCC is to give network numbers to the various insert: <br />
service providers and NICs. The NICs and NOCs can then reassign the insert: <br />
actual IP network numbers to organisations requesting IP network insert: <br />
numbers. insert: <br />
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Class B Network Number Allocation Procedure insert: <br />
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Service providers can request Class B network numbers on a one-by-one insert: <br />
basis from the RIPE NCC. Because class B address space is a critical insert: <br />
resource, a request for a class B network number must be accompanied by one or more network operators with a single clearly defined routing policy. When exchanging exterior routing information, each AS is identified by a unique number. Exterior routing protocols such as BGP, described in delete: <a href="ftp://ftp.ripe.net/rfc/rfc1771.txt"> RFC1771 delete: </a> , "A Border Gateway Protocol 4 (BGP-4)", are used to exchange routing information between Autonomous Systems. An AS insert: <br />
a justification in terms of the requesting organisation's size, current insert: <br />
network and expected network growth. The requestor should also make insert: <br />
clear why they cannot use a block of class C network numbers to achieve insert: <br />
their goals. The RIPE NCC will normally use some interior gateway protocol to exchange routing information on its internal networks. delete: </p> delete: <p class="western"> delete: </p> delete: <h3> delete: <a name="AssignmentCriteria"> delete: </a> 2.0 Assignment Criteria delete: </h3> delete: <p class="western"> In order to help decrease global routing complexity, a new AS Number should be used only if a new external routing policy is required, see delete: <a href="ftp://ftp.ripe.net/rfc/rfc1930.txt"> RFC1930 delete: </a> . delete: </p> delete: <p class="western"> A network must be multihomed in order to qualify for an AS Number. delete: </p> delete: <p class="western"> When requesting an AS Number the routing policy of the Autonomous System must be provided. The new unique routing policy should be defined in RPSL language, as used in the RIPE Database. delete: </p> delete: <p class="western"> review requests using the same standards insert: <br />
as any other Internet Registry, particularly the US NIC. insert: <br />
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Class C Allocation Procedures insert: <br />
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NICs and NOCs accepting a block of class C numbers agree to adhere to insert: <br />
the following procedures: insert: <br />
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A) The RIPE NCC will assign the AS Number directly to the End User upon a complete class C blocks to individual NICs insert: <br />
and NOCs. They can be requested from <hostmaster@ripe.net>. insert: <br />
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B) In order to prevent implementation problems, network numbers ending insert: <br />
with 0 or 255 should NOT be reassigned. insert: <br />
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C) Full information about reassigned network numbers must be reported insert: <br />
back to the RIPE NCC in full RIPE database format (ref ripe-13). insert: <br />
The complete entries should be sent immediately after reassignment to insert: <br />
<assign@ripe.net>. insert: <br />
The RIPE NCC is ready to accept block entries for the RIPE database. insert: <br />
For block syntax, please contact the RIPE NCC. insert: <br />
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D) Reassignment of class C network numbers should be done in a manner insert: <br />
that facilitates Supernetting (see next section). insert: <br />
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E) Requests for network numbers should be reasonable. All NICs and NOCs insert: <br />
should prevent stockpiling of network numbers. insert: <br />
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F) On first request properly submitted to the RIPE NCC either directly from the RIPE NCC, the class C network numbers not insert: <br />
yet reassigned, must be returned to the RIPE NCC. insert: <br />
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Supernetting insert: <br />
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NICs and NOCs reassigning IP network numbers are urgently requested to insert: <br />
read the Supernetting proposal by Vince Fuller et al. This document can insert: <br />
be obtained from the rfc section of the RIPE document store or through a sponsoring LIR. AS Number assignments are subject to the policies described in the RIPE NCC document entitled β€œ delete: <a href="http://www.ripe.net/publications/docs/contract-req" data-linktype="external" data-val="http://www.ripe.net/publications/docs/contract-req"> Contractual Requirements for Provider Independent Resource Holders in the RIPE NCC Service Region delete: </a> ”. delete: </p> delete: <p class="western"> delete: </p> delete: <h3> delete: <strong> delete: <a name="Returning"> delete: </a> 3.0 Returning AS Numbers delete: </strong> delete: </h3> delete: <p class="western"> other RFC insert: <br />
servers. It is called rfc1338.txt. insert: <br />
The Supernetting proposal was made to reduce the increase of routing insert: <br />
table size in the current Internet. It proposes to create a hierarchy insert: <br />
of IP network numbers, which can then be aggregated resulting in less insert: <br />
routing table entries in routing equipment. While this proposal has not insert: <br />
been formally adopted we expect that something at least along the same insert: <br />
principle will be implemented in the near future. insert: <br />
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Here is how it works: insert: <br />
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If an organisation no longer uses the AS Number, it should be returned to the public pool of AS Numbers. The RIPE NCC A needs 8 class C network numbers, the numbers should insert: <br />
be given out in such a way that the routing information for each of insert: <br />
these 8 networks could appear as one entry with the correct mask in insert: <br />
routers. insert: <br />
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More concretely: insert: <br />
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Service provider S hands out networks 192.24.8 through 192.24.15 to insert: <br />
organisation A. These networks can then reassign the AS Number to another organisation. delete: </p> delete: <p class="western"> delete: </p> delete: <h3> delete: <strong> delete: <a name="Transferring"> delete: </a> 4.0 Transferring AS Numbers delete: </strong> delete: </h3> delete: <p> The transfer of Internet number resources is governed by the RIPE Document, " delete: <a href="http://www.ripe.net/publications/docs/transfer-policies" data-val="http://www.ripe.net/publications/docs/transfer-policies" data-linktype="external"> RIPE Resource Transfer Policies delete: </a> ". delete: </p> delete: <p> delete: </p> delete: <h3> delete: <strong> delete: <a name="ASnumbers"> delete: </a> 5.0 32-bit AS Numbers delete: </strong> delete: </h3> delete: <p> The RIPE NCC assigns 32-bit AS Numbers according to the following timeline: delete: </p> delete: <ul> delete: <li> From 1 January 2007 the RIPE NCC will process applications that specifically request 32-bit only AS Numbers (AS Numbers appear in routing equipment as a insert: <br />
supernet route to 192.24.8 with mask 255.255.248.0. This way 8 class C insert: <br />
network numbers appear as one routing table entry. insert: <br />
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The guidelines that can be derived from the Supernetting proposal are: insert: <br />
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A) Service providers should reserve blocks of class C network numbers from insert: <br />
their allocation for each organisations requesting class C network numbers. insert: <br />
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B) The size of these blocks should always be a power of 2. insert: <br />
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C) The numbers in these blocks should be contiguous. insert: <br />
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D) The blocks should start on bit boundaries. insert: <br />
(ie powers of 2, AND multiples of the block size) insert: <br />
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E) The blocks reserved for an organisation should be sufficient for a insert: <br />
reasonable expected growth over the next few years. insert: <br />
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F) Multi-homed organizations may obtain address space from one of their insert: <br />
providers, the RIPE NCC, or the global NIC, as is appropriate to their insert: <br />
network configuration. These organisations are strongly encouraged to insert: <br />
contact the RIPE NCC for guidance. insert: <br />
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If you have any questions concerning this, please do not be represented with 16 bits) and assign such AS Numbers as requested by the applicant. In the absence of any specific request for a 32-bit only AS Number, the RIPE NCC will assign a 16-bit AS Number. delete: </li> delete: </ul> delete: <ul> delete: <li> From 1 January 2009 the RIPE NCC will process applications that specifically request 16-bit AS Numbers and assign such AS Numbers as requested by the applicant. In the absence of any specific request for a 16-bit AS Number, the RIPE NCC will assign a 32-bit only AS Number. delete: </li> delete: </ul> delete: <ul> delete: <li> From 1 January 2010 the RIPE NCC will cease to make any distinction between 16-bit AS Numbers and 32-bit only AS Numbers, and it will operate AS Number assignments from an undifferentiated 32-bit AS Number allocation pool. delete: </li> delete: </ul> delete: <p> delete: <strong> delete: </strong> hesitate to insert: <br />
call or mail us at ncc@ripe.net.

delete: <h3> delete: <strong> delete: <a name="Registration"> delete: </a> 6.0 Registration delete: </strong> delete: </h3> delete: <p> The RIPE NCC will register the resources issued in the RIPE Database. delete: </p> delete: <p> delete: <strong> delete: </strong> delete: </p> delete: <h3> delete: <strong> delete: <a name="References"> delete: </a> 7.0 References delete: </strong> delete: </h3> delete: <p class="western"> [RFC1771] "A Border Gateway Protocol 4 (BGP-4)" delete: <a href="http://www.ietf.org/rfc/rfc1771.txt"> http://www.ietf.org/rfc/rfc1771.txt delete: </a> delete: </p> delete: <p class="western"> [RFC1930] " Guidelines for creation, selection, and registration of an Autonomous System (AS)" delete: <a href="http://www.ietf.org/rfc/rfc1930.txt"> http://www.ietf.org/rfc/rfc1930.txt delete: </a> delete: </p> delete: <p class="western"> [RFC2026] "The Internet Standards Process -- Revision 3 IETF Experimental RFC delete: <a href="http://www.ietf.org/rfc/rfc2026.txt"> http://www.ietf.org/rfc/rfc2026.txt delete: </a> see Sec. 4.2.1 delete: </p> delete: <p class="western"> delete: </p> delete: <h3> delete: <strong> delete: <a name="Attribution"> delete: </a> 8.0 Attribution delete: </strong> delete: </h3> delete: <p class="western"> This document is compiled from policies developed by the RIPE community. delete: </p> delete: <p class="western"> The following people actively contributed by making proposals through the RIPE Policy Development Process: delete: </p> delete: <p class="western"> Nick Hilliard, Geoff Huston delete: </p> delete: <p class=" "> delete: <strong> delete: </strong> delete: </p> delete: <p class="western"> delete: </p>
Autonomous System (AS) Number Assignment Policies RIPE NCC Internet Numbers Registration Procedures