rfc2050.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

          very large, for example, the network prefix required to
          cover the request is of length /18 or shorter.

   All other requestors should contact its ISP for address space or
   utilize the addresses reserved for non-connected networks described
   in RFC1918 until an Internet connection is established.  Note that
   addresses issued directly from the IRs,(non-provider based), are the
   least likely to be routable across the Internet.

3.1  Common Registry Requirements

   Because the number of available IP addresses on the Internet is
   limited, the utilization rate of address space will be a key factor
   in network number assignment.  Therefore, in the best interest of the
   Internet as a whole, specific guidelines have been created to govern
   the assignment of addresses based on utilization rates.

   Although topological issues may make exceptions necessary, the basic
   criteria that should be met to receive network numbers are listed
   below:

                25% immediate utilization rate
                50% utilization  rate within 1 year




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   The utilization rate above is to be used as a guideline, there may be
   be occasions when the 1 year rate does not fall exactly in this
   range.  Organizations must exhibit a high confidence level in its 1
   year utilization rate and supply documentation to justify the level
   of confidence.

   Organizations will be assigned address space based on immediate
   utilization plus 1 year projected utilization.  A prefix longer than
   /24 may be issued if deemed appropriate.  Organizations with less
   than 128 hosts will not be issued an IP address directly from the
   IRs.  Organizations may be issued a prefix longer than /24 if the
   organization can provide documentation from a registry recognized ISP
   indicating the ISP will accept the long prefix for injection into the
   global routing system.

   Exceptions to the criteria will not be made based on insufficient
   equipment without additional detailed justification.  Organizations
   should implement variable length subnet mask (VLSM) internally to
   maximize the effective utilization of address space.  Address
   assignments will be made under the assumption that VLSM is or will be
   implemented.

   IP addresses are valid as long as the criteria continues to be met.
   The IANA reserves the right to invalidate any IP assignments once it
   is determined the the requirement for the address space no longer
   exists.  In the event of address invalidation, reasonable efforts
   will be made by the appropriate registry to inform the organization
   that the addresses have been returned to the free pool of IPv4
   address space.

3.2  Network Engineering Plans

   Before a registry makes an assignment, it must examine each address
   space request in terms of the requesting organization's networking
   plans.  These plans should be documented, and the following
   information should be included:

      1.  subnetting plans, including subnet masks and number of
          hosts on each subnet for at least one year

      2.  a description of the network topology

      3.  a description of the network routing plans, including the
          routing protocols to be used as well as any limitations.







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   The subnetting plans should include:

      a)  a tabular listing of all subnets on the network

      b)  its associated subnet masks

      c)  the estimated number of hosts

      d)  a brief descriptive remark regarding the subnet.

   If subnetting is not being used, an explanation why it cannot be
   implemented is required.  Care must be taken to ensure that the host
   and subnet estimates correspond to realistic requirements and are not
   based on administrative convenience.

3.3  Previous Assignment History

   To promote increased usage of address space, the registries will
   require an accounting of address space previously assigned to the
   enterprise, if any.  In the context of address space allocation, an
   "enterprise" consists of all divisions and/or subsidiaries falling
   under a common parent organization.  The previous assignment history
   should include all network numbers assigned to the organization, plus
   the network masks for those networks and the number of hosts on each
   (sub-)network.  Sufficient corroborating evidence should be provided
   to allow the assigning registry to be confident that the network
   descriptions provided are accurate.  Routing table efficiency will be
   taken into account by the regional registries and each request will
   be handled on a case by case basis.

3.4  Network Deployment Plans

   In order to assign an appropriate amount of space in the required
   time frame, a registry may request deployment plans for a network.
   Deployment plans should include the number of hosts to be deployed
   per time period, expected network growth during that time period, and
   changes in the network topology that describe the growth.

3.5  Organization Information

   A registry may request that an organization furnish a published
   description verifying that the organization is what it claims to be.
   This information can consist of brochures, documents of
   incorporation, or similar published material.







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3.6  Expected Utilization Rate

   As stated in the foregoing text, one of the key factors in
   determining how much address space is appropriate for an organization
   is the expected utilization rate of the network.  The expected
   utilization rate is the number of hosts connected to the network
   divided by the total number of hosts possible on the network.  In
   addition, the estimated number of hosts should be projected over a
   reasonable time frame, i.e., one in which the requesting enterprise
   has a high level of confidence.  The minimal utilization rate is set
   by the IANA and may be changed at any time.  New utilization rates
   may be enforced by the regional registries prior to updating the
   written policy.

4.  Operational Guidelines For Registries

   1.  Regional Registries provide registration services as its
       primary function.  Therefore, regional registries may charge some
       fee for services rendered, generally in relation to the cost of
       providing those services.

   2.  Regardless of the source of its address space, sub-registries
       (Local IRs, ISPs, etc.) must adhere to the guidelines of its
       regional registry.  In turn, it must also ensure that its
       customers follow those guidelines.

   3.  To maximize the effective use of address space, IP addresses need
       to be assigned/allocated in classless blocks.  With this in mind,
       assignments will not be made in Class Cs or Bs but by prefix
       length.  Consequently, an organization that would have been
       assigned a Class B in the past will now be assigned a /16 prefix,
       regardless of the actual address class.

   4.  All IP address requests are subject to audit and verification
       by any means deemed appropriate by the regional registry.
       If any assignment is found to be based on false information,
       the registry may invalidate the request and return the
       assigned addresses back to the pool of free addresses for
       later assignment.

   5.  Due to technical and implementation constraints on the Internet
       routing system and the possibility of routing overload, major
       transit providers may need to impose certain restrictions to
       reduce the number of globally advertised routes.  This may
       include setting limits on the size of CIDR prefixes added to
       the routing tables, filtering of non-aggregated routes, etc.
       Therefore, addresses obtained directly from regional registry
       (provider-independent, also known as portable) are not



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       guaranteed routable on the Internet.

   6.  Information provided to request address space is often considered
       sensitive by the requesting  organization.  The assigning
       registry must treat as confidential any and all information
       that the requesting organization specifically indicates as
       sensitive.  When a requesting organization does not have
       assurance of privacy, the parent of the assigning registry may
       be required to do the assignment.  In such cases, the parent
       registry will provide the assigning registry with information
       regarding the appropriate amount of address space to allocate.

   7.  The transfer of IP addresses from one party to another must be
       approved by the regional registries.  The party trying to obtain
       the IP address must meet the same criteria as if they were
       requesting an IP address directly from the IR.

5.  In-ADDR.ARPA Domain Maintenance

   The regional registries will be responsible for maintaining IN-
   ADDR.ARPA records only on the parent blocks of IP addresses issued
   directly to the ISPs or those CIDR blocks of less than /16.  Local
   IRs/ISPs with a prefix length of /16 or shorter will be responsible
   for maintaining all IN-ADDR.ARPA resource records for its customers.

   IN-ADDR.ARPA resource records for networks not associated with a
   specific provider will continue to be maintained by the regional
   registry.

6.  Right to Appeal

   If an organization feels that the registry that assigned its address
   has not performed its task in the requisite manner, the organization
   has the right of appeal to the parent registry.

   In such cases, the assigning registry shall make available all
   relevant documentation to the parent registry, and the decision of
   the parent registry shall be considered final (barring additional
   appeals to the parent registry's parent).  If necessary, after
   exhausting all other avenues, the appeal may be forwarded to IANA for
   a final decision.  Each registry must, as part of their policy,
   document and specify how to appeal a registry assignment decision.









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7.  References

   [RFC 1519] Fuller, V., Li, T., Yu, J., and K. Varadhan,
      "Classless Inter- Domain Routing (CIDR): an Address
      Assignment and Aggregation Strategy", September 1993.

   [RFC 1518] Rekhter, Y., and T. Li, "An Architecture for IP
      Address Allocation with CIDR", September 1993.

   [RFC 1918] Rekhter, Y., Moskowitz, B., Karrenberg, D., and
      G. de Groot, "Address Allocation for Private Internets",
      February 1996.

   [RFC 1814] Gerich, E., "Unique Addresses are Good", June 1995.

   [RFC 1900] Carpenter, B., and Y. Rekhter, "Renumbering Needs Work",
      February 1996.

8. Security Considerations

   Security issues are not discussed in this memo.






























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9. Authors' Addresses

   Kim Hubbard
   InterNIC Registration Services
   c/o Network Solutions
   505 Huntmar Park Drive
   Herndon, VA 22070

   Phone: [phone]
   EMail: [e-mail]

   Mark Kosters
   InterNIC Registration Services
   c/o Network Solutions
   505 Huntmar Park Drive
   Herndon, VA 22070

   Phone: [phone]
   EMail: [e-mail]

   David Conrad
   Asia Pacific Network Information Center
   c/o United Nations University
   53-70 Jingumae 5-chome,
   Shibuya-ku, Tokyo 150
   JP

   Phone: [phone]
   EMail: [e-mail]

   Daniel Karrenberg
   RIPE NCC
   Kruislaan 409
   SJ Amsterdam NL-1098
   NL

   Phone: [phone]
   EMail: [e-mail]

   Jon Postel
   USC/Information Sciences Institute
   4676 Admiralty Way
   Marina del Rey, CA  90292

   Phone: [phone]
   EMail: [e-mail]





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