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Internet Engineering Task Force (IETF)                           J. Weil
Request for Comments: 6598                             Time Warner Cable
BCP: 153                                                    V. Kuarsingh
Updates: 5735                                      Rogers Communications
Category: Best Current Practice                                C. Donley
ISSN: 2070-1721                                                CableLabs
                                                         C. Liljenstolpe
                                                           Telstra Corp.
                                                              M. Azinger
                                                 Frontier Communications
                                                              April 2012


           IANA-Reserved IPv4 Prefix for Shared Address Space

Abstract

   This document requests the allocation of an IPv4 /10 address block to
   be used as Shared Address Space to accommodate the needs of Carrier-
   Grade NAT (CGN) devices.  It is anticipated that Service Providers
   will use this Shared Address Space to number the interfaces that
   connect CGN devices to Customer Premises Equipment (CPE).

   Shared Address Space is distinct from RFC 1918 private address space
   because it is intended for use on Service Provider networks.
   However, it may be used in a manner similar to RFC 1918 private
   address space on routing equipment that is able to do address
   translation across router interfaces when the addresses are identical
   on two different interfaces.  Details are provided in the text of
   this document.

   This document details the allocation of an additional special-use
   IPv4 address block and updates RFC 5735.

Status of This Memo

   This memo documents an Internet Best Current Practice.

   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
   BCPs 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/rfc6598.




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IESG Note

   A number of operators have expressed a need for the special-purpose
   IPv4 address allocation described by this document.  During
   deliberations, the IETF community demonstrated very rough consensus
   in favor of the allocation.

   While operational expedients, including the special-purpose address
   allocation described in this document, may help solve a short-term
   operational problem, the IESG and the IETF remain committed to the
   deployment of IPv6.

Copyright Notice

   Copyright (c) 2012 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1. Introduction ....................................................3
   2. Requirements Language ...........................................3
   3. Alternatives to Shared Address Space ............................3
   4. Use of Shared CGN Space .........................................4
   5. Risk ............................................................5
      5.1. Analysis ...................................................5
      5.2. Empirical Data .............................................6
   6. Security Considerations .........................................7
   7. IANA Considerations .............................................8
   8. References ......................................................8
      8.1. Normative References .......................................8
      8.2. Informative References .....................................9
   Appendix A. Acknowledgments .......................................10









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1.  Introduction

   IPv4 address space is nearly exhausted.  However, ISPs must continue
   to support IPv4 growth until IPv6 is fully deployed.  To that end,
   many ISPs will deploy a Carrier-Grade NAT (CGN) device, such as that
   described in [RFC6264].  Because CGNs are used on networks where
   public address space is expected, and currently available private
   address space causes operational issues when used in this context,
   ISPs require a new IPv4 /10 address block.  This address block will
   be called the "Shared Address Space" and will be used to number the
   interfaces that connect CGN devices to Customer Premises Equipment
   (CPE).

   Shared Address Space is similar to [RFC1918] private address space in
   that it is not globally routable address space and can be used by
   multiple pieces of equipment.  However, Shared Address Space has
   limitations in its use that the current [RFC1918] private address
   space does not have.  In particular, Shared Address Space can only be
   used in Service Provider networks or on routing equipment that is
   able to do address translation across router interfaces when the
   addresses are identical on two different interfaces.

   This document requests the allocation of an IPv4 /10 address block to
   be used as Shared Address Space.  In conversations with many ISPs, a
   /10 is the smallest block that will allow them to deploy CGNs on a
   regional basis without requiring nested CGNs.  For instance, as
   described in [ISP-SHARED-ADDR], a /10 is sufficient to service Points
   of Presence in the Tokyo area.

   This document details the allocation of an additional special-use
   IPv4 address block and updates [RFC5735].

2.  Requirements Language

   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 RFC 2119 [RFC2119].

3.  Alternatives to Shared Address Space

   The interfaces that connect CGN devices to CPE might conceivably be
   numbered from any of the following address spaces:

   o  legitimately assigned globally unique address space

   o  usurped globally unique address space (i.e., squat space)





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   o  [RFC1918] space

   o  Shared Address Space

   A Service Provider can number the interfaces in question from
   legitimately assigned globally unique address space.  While this
   solution poses the fewest problems, it is impractical because
   globally unique IPv4 address space is in short supply.  While the
   Regional Internet Registries (RIRs) have enough address space to
   allocate a single /10 to be shared by all Service Providers, they do
   not have enough address space to make a unique assignment to each
   Service Provider.

   Service Providers MUST NOT number the interfaces in question from
   usurped globally unique address space (i.e., squat space).  If a
   Service Provider leaks advertisements for squat space into the global
   Internet, the legitimate holders of that address space may be
   adversely impacted, as would those wishing to communicate with them.
   Even if the Service Provider did not leak advertisements for squat
   space, the Service Provider and its subscribers might lose
   connectivity to the legitimate holders of that address space.

   A Service Provider can number the interfaces in question from
   [RFC1918] space if at least one of the following conditions is true:

   o  The Service Provider knows that the CPE/NAT works correctly when
      the same [RFC1918] address block is used on both its inside and
      outside interfaces.

   o  The Service Provider knows that the [RFC1918] address block that
      it uses to number interfaces between the CGN and CPE is not used
      on the subscriber side of the CPE.

   Unless at least one of the conditions above is true, the Service
   Provider cannot safely use [RFC1918] address space and must resort to
   Shared Address Space.  This is typically the case in an unmanaged
   service, where subscribers provide their own CPE and number their own
   internal network.

4.  Use of Shared CGN Space

   Shared Address Space is IPv4 address space designated for Service
   Provider use with the purpose of facilitating CGN deployment.  Also,
   Shared Address Space can be used as additional non-globally routable
   space on routing equipment that is able to do address translation
   across router interfaces when the addresses are identical on two
   different interfaces.




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   Devices MUST be capable of performing address translation when
   identical Shared Address Space ranges are used on two different
   interfaces.

   Packets with Shared Address Space source or destination addresses
   MUST NOT be forwarded across Service Provider boundaries.  Service
   Providers MUST filter such packets on ingress links.  One exception
   to this paragraph's proscription is in the case of business
   relationships, such as hosted CGN services.

   When running a single DNS infrastructure, Service Providers MUST NOT
   include Shared Address Space in zone files.  When running a split DNS
   infrastructure, Service Providers MUST NOT include Shared Address
   Space in external-facing zone files.

   Reverse DNS queries for Shared Address Space addresses MUST NOT be
   forwarded to the global DNS infrastructure.  DNS Providers SHOULD
   filter requests for Shared Address Space reverse DNS queries on
   recursive nameservers.  This is done to avoid having to set up
   something similar to AS112.net for [RFC1918] private address space
   that a host has incorrectly sent for a DNS that reverse-maps queries
   on the public Internet [RFC6304].

   Because CGN service requires non-overlapping address space on each
   side of the home NAT and CGN, entities using Shared Address Space for
   purposes other than for CGN service, as described in this document,
   are likely to experience problems implementing or connecting to CGN
   service at such time as they exhaust their supply of public IPv4
   addresses.

5.  Risk

5.1.  Analysis

   Some existing applications discover the outside address of their
   local CPE, determine whether the address is reserved for special use,
   and behave differently based on that determination.  If a new IPv4
   address block is reserved for special use and that block is used to
   number CPE outside interfaces, some of the above-mentioned
   applications may fail.

   For example, assume that an application requires its peer (or some
   other device) to initiate an incoming connection directly with its
   CPE's outside address.  That application discovers the outside
   address of its CPE and determines whether that address is reserved
   for special use.  If the address is reserved for special use, the
   application rightly concludes that the address is not reachable from




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   the global Internet and behaves in one manner.  If the address is not
   reserved for special use, the application assumes that the address is
   reachable from the global Internet and behaves in another manner.

   While the assumption that a non-special-use address is reachable from
   the global Internet is generally safe, it is not always true (e.g.,
   when the CPE outside interface is numbered from globally unique
   address space but that address is not advertised to the global
   Internet as when it is behind a CGN).  Such an assumption could cause
   certain applications to behave incorrectly in those cases.

5.2.  Empirical Data

   The primary motivation for the allocation of Shared Address Space is
   as address space for CGNs; the use and impact of CGNs has been
   previously described in [RFC6269] and [NAT444-IMPACTS].  Some of the
   services adversely impacted by CGNs are as follows:

   1.  Console gaming -- some games fail when two subscribers using the
       same outside public IPv4 address try to connect to each other.

   2.  Video streaming -- performance is impacted when using one of
       several popular video-streaming technologies to deliver multiple
       video streams to users behind particular CPE routers.

   3.  Peer-to-peer -- some peer-to-peer applications cannot seed
       content due to the inability to open incoming ports through the
       CGN.  Likewise, some SIP client implementations cannot receive
       incoming calls unless they first initiate outgoing traffic or
       open an incoming port through the CGN using the Port Control
       Protocol (PCP) [PCP-BASE] or a similar mechanism.

   4.  Geo-location -- geo-location systems identify the location of the
       CGN server, not the end host.

   5.  Simultaneous logins -- some websites (particularly banking and
       social-networking websites) restrict the number of simultaneous
       logins per outside public IPv4 address.

   6.  6to4 -- 6to4 requires globally reachable addresses and will not
       work in networks that employ addresses with limited topological
       span, such as those employing CGNs.

   Based on testing documented in [NAT444-IMPACTS], the CGN impacts on
   items 1-5 above are comparable regardless of whether globally unique,
   Shared Address Space, or [RFC1918] addresses are used.  There is,
   however, a difference between the three alternatives in the treatment
   of 6to4.



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   As described in [RFC6343], CPE routers do not attempt to initialize
   6to4 tunnels when they are configured with [RFC1918] or [RFC5735] WAN
   addresses.  When configured with globally unique or Shared Address
   Space addresses, such devices may attempt to initiate 6to4, which
   would fail.  Service Providers can mitigate this issue using 6to4
   Provider Managed Tunnels [6to4-PMT] or blocking the route to
   192.88.99.1 and generating an IPv4 'destination unreachable' message
   [RFC6343].  When the address range is well-defined, as with Shared
   Address Space, CPE router vendors can include Shared Address Space in
   their list of special-use addresses (e.g., [RFC5735]) and treat
   Shared Address Space similarly to [RFC1918] space.  When the CGN-CPE
   address range is not well-defined, as in the case of globally unique
   space, it will be more difficult for CPE router vendors to mitigate
   this issue.

   Thus, when comparing the use of [RFC1918] and Shared Address Space,
   Shared Address Space poses an additional impact on 6to4 connectivity,
   which can be mitigated by Service Provider or CPE router vendor
   action.  On the other hand, the use of [RFC1918] address space poses
   more of a challenge vis-a-vis Shared Address Space when the
   subscriber and Service Provider use overlapping [RFC1918] space,
   which will be outside the Service Provider's control in the case of
   unmanaged service.  Service Providers have indicated that it is more
   challenging to mitigate the possibility of overlapping [RFC1918]
   address space on both sides of the CPE router than it is to mitigate
   the 6to4 impacts of Shared Address Space.

6.  Security Considerations

   Similar to other [RFC5735] special-use IPv4 addresses, Shared Address
   Space does not directly raise security issues.  However, the Internet
   does not inherently protect against abuse of these addresses.
   Attacks have been mounted that depend on the unexpected use of
   similar special-use addresses.  Network operators are encouraged to
   review this document and determine what security policies should be
   associated with this address block within their specific operating
   environments.  They should consider including Shared Address Space in
   Ingress Filter lists [RFC3704], unless their Internet service
   incorporates a CGN.












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   To mitigate potential misuse of Shared Address Space, except where
   required for hosted CGN service or a similar business relationship,

   o  routing information about Shared Address Space networks MUST NOT
      be propagated across Service Provider boundaries.  Service
      Providers MUST filter incoming advertisements regarding Shared
      Address Space.

   o  packets with Shared Address Space source or destination addresses
      MUST NOT be forwarded across Service Provider boundaries.  Service
      Providers MUST filter such packets on ingress links.

   o  Service Providers MUST NOT include Shared Address Space in
      external-facing DNS zone files.

   o  reverse DNS queries for Shared Address Space addresses MUST NOT be
      forwarded to the global DNS infrastructure.

   o  DNS Providers SHOULD filter requests for Shared Address Space
      reverse DNS queries on recursive nameservers.

7.  IANA Considerations

   IANA has recorded the allocation of an IPv4 /10 for use as Shared
   Address Space.

   The Shared Address Space address range is 100.64.0.0/10.

8.  References

8.1.  Normative References

   [RFC1918]  Rekhter, Y., Moskowitz, R., Karrenberg, D., de Groot, G.,
              and E. Lear, "Address Allocation for Private Internets",
              BCP 5, RFC 1918, February 1996.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC5735]  Cotton, M. and L. Vegoda, "Special Use IPv4 Addresses",
              BCP 153, RFC 5735, January 2010.










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8.2.  Informative References

   [6to4-PMT] Kuarsingh, V., Ed., Lee, Y., and O. Vautrin, "6to4
              Provider Managed Tunnels", Work in Progress,
              February 2012.

   [ISP-SHARED-ADDR]
              Yamagata, I., Miyakawa, S., Nakagawa, A., Yamaguchi, J.,
              and H. Ashida, "ISP Shared Address", Work in Progress,
              January 2012.

   [NAT444-IMPACTS]
              Donley, C., Howard, L., Kuarsingh, V., Berg, J., and J.
              Doshi, "Assessing the Impact of Carrier-Grade NAT on
              Network Applications", Work in Progress, November 2011.

   [PCP-BASE] Wing, D., Ed., Cheshire, S., Boucadair, M., Penno, R., and
              P. Selkirk, "Port Control Protocol (PCP)", Work
              in Progress, March 2012.

   [RFC3704]  Baker, F. and P. Savola, "Ingress Filtering for Multihomed
              Networks", BCP 84, RFC 3704, March 2004.

   [RFC6264]  Jiang, S., Guo, D., and B. Carpenter, "An Incremental
              Carrier-Grade NAT (CGN) for IPv6 Transition", RFC 6264,
              June 2011.

   [RFC6269]  Ford, M., Ed., Boucadair, M., Durand, A., Levis, P., and
              P. Roberts, "Issues with IP Address Sharing", RFC 6269,
              June 2011.

   [RFC6304]  Abley, J. and W. Maton, "AS112 Nameserver Operations",
              RFC 6304, July 2011.

   [RFC6343]  Carpenter, B., "Advisory Guidelines for 6to4 Deployment",
              RFC 6343, August 2011.















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Appendix A.  Acknowledgments

   Thanks to the following people (in alphabetical order) for their
   guidance and feedback:

      Stan Barber
      John Brzozowski
      Isaiah Connell
      Greg Davies
      Owen DeLong
      Kirk Erichsen
      Wes George
      Chris Grundemann
      Tony Hain
      Philip Matthews
      John Pomeroy
      Barbara Stark
      Jean-Francois Tremblay
      Leo Vegoda
      Steven Wright
      Ikuhei Yamagata






























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Authors' Addresses

   Jason Weil
   Time Warner Cable
   13820 Sunrise Valley Drive
   Herndon, VA  20171
   USA

   EMail: jason.weil@twcable.com


   Victor Kuarsingh
   Rogers Communications
   8200 Dixie Road
   Brampton, ON  L6T 0C1
   Canada

   EMail: victor.kuarsingh@gmail.com


   Chris Donley
   CableLabs
   858 Coal Creek Circle
   Louisville, CO  80027
   USA

   EMail: c.donley@cablelabs.com


   Christopher Liljenstolpe
   Telstra Corp.
   7/242 Exhibition Street
   Melbourne, VIC  316
   Australia

   Phone: +61 3 8647 6389
   EMail: cdl@asgaard.org


   Marla Azinger
   Frontier Communications
   Vancouver, WA
   USA

   Phone: +1.360.513.2293
   EMail: marla.azinger@frontiercorp.com





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=========================================================================





Internet Engineering Task Force (IETF)                         M. Cotton
Request for Comments: 6890                                     L. Vegoda
BCP: 153                                                           ICANN
Obsoletes: 4773, 5156, 5735, 5736                         R. Bonica, Ed.
Category: Best Current Practice                         Juniper Networks
ISSN: 2070-1721                                              B. Haberman
                                                                     JHU
                                                              April 2013


                 Special-Purpose IP Address Registries

Abstract

   This memo reiterates the assignment of an IPv4 address block
   (192.0.0.0/24) to IANA.  It also instructs IANA to restructure its
   IPv4 and IPv6 Special-Purpose Address Registries.  Upon
   restructuring, the aforementioned registries will record all special-
   purpose address blocks, maintaining a common set of information
   regarding each address block.

   This memo obsoletes RFCs 4773, 5156, 5735, and 5736.

Status of This Memo

   This memo documents an Internet Best Current Practice.

   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
   BCPs 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/rfc6890.















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Copyright Notice

   Copyright (c) 2013 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1. Introduction ....................................................2
   2. IANA Considerations .............................................3
      2.1. Assignment of an IPv4 Address Block to IANA ................3
      2.2. Restructuring of the IPv4 and IPv6 Special-Purpose
           Address ....................................................4
           2.2.1. Information Requirements ............................4
           2.2.2. IPv4 Special-Purpose Address Registry Entries .......6
           2.2.3. IPv6 Special-Purpose Address Registry Entries ......14
   3. Security Considerations ........................................20
   4. Acknowledgements ...............................................20
   5. Informative References .........................................20

1.  Introduction

   In order to support new protocols and practices, the IETF
   occasionally reserves an address block for a special purpose.  For
   example, [RFC1122] reserves an IPv4 address block (0.0.0.0/8) to
   represent the local (i.e., "this") network.  Likewise, [RFC4291]
   reserves an IPv6 address block (fe80::/10) to represent link-scoped
   unicast addresses.

   Periodically, the IETF publishes an RFC that catalogs special-purpose
   address blocks.  Currently, [RFC5735] catalogs all IPv4 special-
   purpose address blocks and [RFC5156] catalogs all IPv6 special-
   purpose address blocks.

   [RFC5736] assigns an IPv4 address block (192.0.0.0/24) to IANA and
   instructs IANA to allocate special-purpose address blocks from this
   space.  [RFC5736] also instructs IANA to create an IPv4 Special-
   Purpose Address Registry that records allocations from this address




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   space.  However, [RFC5736] does not instruct IANA to record special-
   purpose address block reservations from outside of the aforementioned
   space in the IPv4 Special-Purpose Address Registry.

   Likewise, [RFC2928] assigns an IPv6 address block (2001:0000::/23) to
   IANA and instructs IANA to allocate special-purpose address blocks
   from this space.  [RFC4773] instructs IANA to create an IPv6 Special-
   Purpose Address Registry that records allocations from this address
   space.  However, [RFC4773] does not instruct IANA to record special-
   purpose address block reservations from outside of the aforementioned
   space in the IPv6 Special-Purpose Address Registry.

   This memo reiterates the assignment of an IPv4 address block
   (192.0.0.0/24) to IANA.  It also instructs IANA to restructure its
   IPv4 and IPv6 Special-Purpose Address Registries.  Specifically, this
   memo instructs IANA to record all special-purpose address blocks in
   the aforementioned registries.  These include, but are not limited
   to, IPv4 allocations from 192.0.0.0/24 and IPv6 allocations from
   2001:0000::/23.  Furthermore, this memo defines:

   o  a common set of information that the registries will maintain
      regarding each special-purpose address block

   o  a common set of requirements for future entries

   When the aforementioned registries include all special-purpose
   address blocks, [RFC5735] and [RFC5156] will become redundant with
   the registries.  Therefore, this memo obsoletes [RFC5735] and
   [RFC5156].  Because this memo reiterates the assignment of
   192.0.0.0/24 to IANA, and because it restructures the IPv4 Special-
   Purpose Address Registry, it obsoletes [RFC5736].  Finally, because
   this memo restructures the IPv6 Special-Purpose Address Registry, it
   obsoletes [RFC4773].

2.  IANA Considerations

2.1.  Assignment of an IPv4 Address Block to IANA

   Table 7 of this document records the assignment of an IPv4 address
   block (192.0.0.0/24) to IANA for IETF protocol assignments.  This
   address allocation to IANA is intended to support IETF protocol
   assignments.  A more general view of the roles of IANA with respect
   to address allocation functions is documented in Sections 4.1 and 4.3
   [RFC2860].

   IANA has designated special-purpose address blocks in compliance with
   [RFC2860].




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2.2.  Restructuring of the IPv4 and IPv6 Special-Purpose Address
      Registries

   IANA has restructured the following registries:

      o  IPv4 Special-Purpose Address Registry

      o  IPv6 Special-Purpose Address Registry

   The IPv4 Special-Purpose Address Registry records all IPv4 special-
   purpose address blocks.  These reservations include, but are not
   limited to, allocations from the 192.0.0.0/24 address block.
   Likewise, the IPv6 Special-Purpose Address Registry records all IPv6
   special-purpose address blocks.  These reservations include, but are
   not limited to, allocations from the 2001:0000::/23 address block.

   Section 2.2.1 of this document describes information that both
   registries will maintain for each entry.  Initially, IANA has
   populated the IPv4 Special-Purpose Address Registry with information
   taken from Section 2.2.2 of this document.  Likewise, IANA has
   populated the IPv6 Special-Purpose Address Registry with information
   taken from Section 2.2.3 of this document.

   IANA will update the aforementioned registries as requested in the
   "IANA Considerations" section of a document that has passed IETF
   Review [RFC5226].  The "IANA Considerations" section must include all
   of the information specified in Section 2.2.1 of this document.

2.2.1.  Information Requirements

   The IPv4 and IPv6 Special-Purpose Address Registries maintain the
   following information regarding each entry:

   o  Address Block - A block of IPv4 or IPv6 addresses that has been
      registered for a special purpose.

   o  Name - A descriptive name for the special-purpose address block.

   o  RFC - The RFC through which the special-purpose address block was
      requested.

   o  Allocation Date - The date upon which the special-purpose address
      block was allocated.

   o  Termination Date - The date upon which the allocation is to be
      terminated.  This field is applicable for limited-use allocations
      only.




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   o  Source - A boolean value indicating whether an address from the
      allocated special-purpose address block is valid when used as the
      source address of an IP datagram that transits two devices.

   o  Destination - A boolean value indicating whether an address from
      the allocated special-purpose address block is valid when used as
      the destination address of an IP datagram that transits two
      devices.

   o  Forwardable - A boolean value indicating whether a router may
      forward an IP datagram whose destination address is drawn from the
      allocated special-purpose address block between external
      interfaces.

   o  Global - A boolean value indicating whether an IP datagram whose
      destination address is drawn from the allocated special-purpose
      address block is forwardable beyond a specified administrative
      domain.

   o  Reserved-by-Protocol - A boolean value indicating whether the
      special-purpose address block is reserved by IP, itself.  This
      value is "TRUE" if the RFC that created the special-purpose
      address block requires all compliant IP implementations to behave
      in a special way when processing packets either to or from
      addresses contained by the address block.

   If the value of "Destination" is FALSE, the values of "Forwardable"
   and "Global" must also be false.























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RFC 6890           Special-Purpose Address Registries         April 2013


2.2.2.  IPv4 Special-Purpose Address Registry Entries

   Tables 1 though 16, below, represent entries with which IANA has
   initially populated the IPv4 Special-Purpose Address Registry.

              +----------------------+----------------------------+
              | Attribute            | Value                      |
              +----------------------+----------------------------+
              | Address Block        | 0.0.0.0/8                  |
              | Name                 | "This host on this network"|
              | RFC                  | [RFC1122], Section 3.2.1.3 |
              | Allocation Date      | September 1981             |
              | Termination Date     | N/A                        |
              | Source               | True                       |
              | Destination          | False                      |
              | Forwardable          | False                      |
              | Global               | False                      |
              | Reserved-by-Protocol | True                       |
              +----------------------+----------------------------+

                    Table 1: "This host on this network"

                    +----------------------+---------------+
                    | Attribute            | Value         |
                    +----------------------+---------------+
                    | Address Block        | 10.0.0.0/8    |
                    | Name                 | Private-Use   |
                    | RFC                  | [RFC1918]     |
                    | Allocation Date      | February 1996 |
                    | Termination Date     | N/A           |
                    | Source               | True          |
                    | Destination          | True          |
                    | Forwardable          | True          |
                    | Global               | False         |
                    | Reserved-by-Protocol | False         |
                    +----------------------+---------------+

                       Table 2: Private-Use Networks













Cotton, et al.            Best Current Practice                 [Page 6]

RFC 6890           Special-Purpose Address Registries         April 2013


                 +----------------------+----------------------+
                 | Attribute            | Value                |
                 +----------------------+----------------------+
                 | Address Block        | 100.64.0.0/10        |
                 | Name                 | Shared Address Space |
                 | RFC                  | [RFC6598]            |
                 | Allocation Date      | April 2012           |
                 | Termination Date     | N/A                  |
                 | Source               | True                 |
                 | Destination          | True                 |
                 | Forwardable          | True                 |
                 | Global               | False                |
                 | Reserved-by-Protocol | False                |
                 +----------------------+----------------------+

                       Table 3: Shared Address Space

              +----------------------+----------------------------+
              | Attribute            | Value                      |
              +----------------------+----------------------------+
              | Address Block        | 127.0.0.0/8                |
              | Name                 | Loopback                   |
              | RFC                  | [RFC1122], Section 3.2.1.3 |
              | Allocation Date      | September 1981             |
              | Termination Date     | N/A                        |
              | Source               | False [1]                  |
              | Destination          | False [1]                  |
              | Forwardable          | False [1]                  |
              | Global               | False [1]                  |
              | Reserved-by-Protocol | True                       |
              +----------------------+----------------------------+

              [1] Several protocols have been granted exceptions to this
                  rule.  For examples, see [RFC4379] and [RFC5884].

                             Table 4: Loopback















Cotton, et al.            Best Current Practice                 [Page 7]

RFC 6890           Special-Purpose Address Registries         April 2013


                    +----------------------+----------------+
                    | Attribute            | Value          |
                    +----------------------+----------------+
                    | Address Block        | 169.254.0.0/16 |
                    | Name                 | Link Local     |
                    | RFC                  | [RFC3927]      |
                    | Allocation Date      | May 2005       |
                    | Termination Date     | N/A            |
                    | Source               | True           |
                    | Destination          | True           |
                    | Forwardable          | False          |
                    | Global               | False          |
                    | Reserved-by-Protocol | True           |
                    +----------------------+----------------+

                            Table 5: Link Local

                    +----------------------+---------------+
                    | Attribute            | Value         |
                    +----------------------+---------------+
                    | Address Block        | 172.16.0.0/12 |
                    | Name                 | Private-Use   |
                    | RFC                  | [RFC1918]     |
                    | Allocation Date      | February 1996 |
                    | Termination Date     | N/A           |
                    | Source               | True          |
                    | Destination          | True          |
                    | Forwardable          | True          |
                    | Global               | False         |
                    | Reserved-by-Protocol | False         |
                    +----------------------+---------------+

                       Table 6: Private-Use Networks


















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RFC 6890           Special-Purpose Address Registries         April 2013


            +----------------------+---------------------------------+
            | Attribute            | Value                           |
            +----------------------+---------------------------------+
            | Address Block        | 192.0.0.0/24 [2]                |
            | Name                 | IETF Protocol Assignments       |
            | RFC                  | Section 2.1 of this document    |
            | Allocation Date      | January 2010                    |
            | Termination Date     | N/A                             |
            | Source               | False                           |
            | Destination          | False                           |
            | Forwardable          | False                           |
            | Global               | False                           |
            | Reserved-by-Protocol | False                           |
            +----------------------+---------------------------------+

              [2] Not usable unless by virtue of a more specific
                  reservation.

                    Table 7: IETF Protocol Assignments

             +----------------------+--------------------------------+
             | Attribute            | Value                          |
             +----------------------+--------------------------------+
             | Address Block        | 192.0.0.0/29                   |
             | Name                 | DS-Lite                        |
             | RFC                  | [RFC6333]                      |
             | Allocation Date      | June 2011                      |
             | Termination Date     | N/A                            |
             | Source               | True                           |
             | Destination          | True                           |
             | Forwardable          | True                           |
             | Global               | False                          |
             | Reserved-by-Protocol | False                          |
             +----------------------+--------------------------------+

                             Table 8: DS-Lite















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RFC 6890           Special-Purpose Address Registries         April 2013


              +----------------------+----------------------------+
              | Attribute            | Value                      |
              +----------------------+----------------------------+
              | Address Block        | 192.0.2.0/24               |
              | Name                 | Documentation (TEST-NET-1) |
              | RFC                  | [RFC5737]                  |
              | Allocation Date      | January 2010               |
              | Termination Date     | N/A                        |
              | Source               | False                      |
              | Destination          | False                      |
              | Forwardable          | False                      |
              | Global               | False                      |
              | Reserved-by-Protocol | False                      |
              +----------------------+----------------------------+

                            Table 9: TEST-NET-1

                  +----------------------+--------------------+
                  | Attribute            | Value              |
                  +----------------------+--------------------+
                  | Address Block        | 192.88.99.0/24     |
                  | Name                 | 6to4 Relay Anycast |
                  | RFC                  | [RFC3068]          |
                  | Allocation Date      | June 2001          |
                  | Termination Date     | N/A                |
                  | Source               | True               |
                  | Destination          | True               |
                  | Forwardable          | True               |
                  | Global               | True               |
                  | Reserved-by-Protocol | False              |
                  +----------------------+--------------------+

                       Table 10: 6to4 Relay Anycast


















Cotton, et al.            Best Current Practice                [Page 10]

RFC 6890           Special-Purpose Address Registries         April 2013


                    +----------------------+----------------+
                    | Attribute            | Value          |
                    +----------------------+----------------+
                    | Address Block        | 192.168.0.0/16 |
                    | Name                 | Private-Use    |
                    | RFC                  | [RFC1918]      |
                    | Allocation Date      | February 1996  |
                    | Termination Date     | N/A            |
                    | Source               | True           |
                    | Destination          | True           |
                    | Forwardable          | True           |
                    | Global               | False          |
                    | Reserved-by-Protocol | False          |
                    +----------------------+----------------+

                      Table 11: Private-Use Networks

                    +----------------------+---------------+
                    | Attribute            | Value         |
                    +----------------------+---------------+
                    | Address Block        | 198.18.0.0/15 |
                    | Name                 | Benchmarking  |
                    | RFC                  | [RFC2544]     |
                    | Allocation Date      | March 1999    |
                    | Termination Date     | N/A           |
                    | Source               | True          |
                    | Destination          | True          |
                    | Forwardable          | True          |
                    | Global               | False         |
                    | Reserved-by-Protocol | False         |
                    +----------------------+---------------+

          Table 12: Network Interconnect Device Benchmark Testing


















Cotton, et al.            Best Current Practice                [Page 11]

RFC 6890           Special-Purpose Address Registries         April 2013


              +----------------------+----------------------------+
              | Attribute            | Value                      |
              +----------------------+----------------------------+
              | Address Block        | 198.51.100.0/24            |
              | Name                 | Documentation (TEST-NET-2) |
              | RFC                  | [RFC5737]                  |
              | Allocation Date      | January 2010               |
              | Termination Date     | N/A                        |
              | Source               | False                      |
              | Destination          | False                      |
              | Forwardable          | False                      |
              | Global               | False                      |
              | Reserved-by-Protocol | False                      |
              +----------------------+----------------------------+

                           Table 13: TEST-NET-2

              +----------------------+----------------------------+
              | Attribute            | Value                      |
              +----------------------+----------------------------+
              | Address Block        | 203.0.113.0/24             |
              | Name                 | Documentation (TEST-NET-3) |
              | RFC                  | [RFC5737]                  |
              | Allocation Date      | January 2010               |
              | Termination Date     | N/A                        |
              | Source               | False                      |
              | Destination          | False                      |
              | Forwardable          | False                      |
              | Global               | False                      |
              | Reserved-by-Protocol | False                      |
              +----------------------+----------------------------+

                           Table 14: TEST-NET-3


















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RFC 6890           Special-Purpose Address Registries         April 2013


                 +----------------------+----------------------+
                 | Attribute            | Value                |
                 +----------------------+----------------------+
                 | Address Block        | 240.0.0.0/4          |
                 | Name                 | Reserved             |
                 | RFC                  | [RFC1112], Section 4 |
                 | Allocation Date      | August 1989          |
                 | Termination Date     | N/A                  |
                 | Source               | False                |
                 | Destination          | False                |
                 | Forwardable          | False                |
                 | Global               | False                |
                 | Reserved-by-Protocol | True                 |
                 +----------------------+----------------------+

                     Table 15: Reserved for Future Use

                 +----------------------+----------------------+
                 | Attribute            | Value                |
                 +----------------------+----------------------+
                 | Address Block        | 255.255.255.255/32   |
                 | Name                 | Limited Broadcast    |
                 | RFC                  | [RFC0919], Section 7 |
                 | Allocation Date      | October 1984         |
                 | Termination Date     | N/A                  |
                 | Source               | False                |
                 | Destination          | True                 |
                 | Forwardable          | False                |
                 | Global               | False                |
                 | Reserved-by-Protocol | False                |
                 +----------------------+----------------------+

                        Table 16: Limited Broadcast


















Cotton, et al.            Best Current Practice                [Page 13]

RFC 6890           Special-Purpose Address Registries         April 2013


2.2.3.  IPv6 Special-Purpose Address Registry Entries

   Tables 17 through 28, below, represent entries with which the IANA
   has initially populated the IPv6 Special-Purpose Address Registry.

                   +----------------------+------------------+
                   | Attribute            | Value            |
                   +----------------------+------------------+
                   | Address Block        | ::1/128          |
                   | Name                 | Loopback Address |
                   | RFC                  | [RFC4291]        |
                   | Allocation Date      | February 2006    |
                   | Termination Date     | N/A              |
                   | Source               | False            |
                   | Destination          | False            |
                   | Forwardable          | False            |
                   | Global               | False            |
                   | Reserved-by-Protocol | True             |
                   +----------------------+------------------+

                        Table 17: Loopback Address

                 +----------------------+---------------------+
                 | Attribute            | Value               |
                 +----------------------+---------------------+
                 | Address Block        | ::/128              |
                 | Name                 | Unspecified Address |
                 | RFC                  | [RFC4291]           |
                 | Allocation Date      | February 2006       |
                 | Termination Date     | N/A                 |
                 | Source               | True                |
                 | Destination          | False               |
                 | Forwardable          | False               |
                 | Global               | False               |
                 | Reserved-by-Protocol | True                |
                 +----------------------+---------------------+

                       Table 18: Unspecified Address













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RFC 6890           Special-Purpose Address Registries         April 2013


                +----------------------+---------------------+
                | Attribute            | Value               |
                +----------------------+---------------------+
                | Address Block        | 64:ff9b::/96        |
                | Name                 | IPv4-IPv6 Translat. |
                | RFC                  | [RFC6052]           |
                | Allocation Date      | October 2010        |
                | Termination Date     | N/A                 |
                | Source               | True                |
                | Destination          | True                |
                | Forwardable          | True                |
                | Global               | True                |
                | Reserved-by-Protocol | False               |
                +----------------------+---------------------+

                  Table 19: IPv4-IPv6 Translation Address

                 +----------------------+---------------------+
                 | Attribute            | Value               |
                 +----------------------+---------------------+
                 | Address Block        | ::ffff:0:0/96       |
                 | Name                 | IPv4-mapped Address |
                 | RFC                  | [RFC4291]           |
                 | Allocation Date      | February 2006       |
                 | Termination Date     | N/A                 |
                 | Source               | False               |
                 | Destination          | False               |
                 | Forwardable          | False               |
                 | Global               | False               |
                 | Reserved-by-Protocol | True                |
                 +----------------------+---------------------+

                       Table 20: IPv4-Mapped Address


















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RFC 6890           Special-Purpose Address Registries         April 2013


              +----------------------+----------------------------+
              | Attribute            | Value                      |
              +----------------------+----------------------------+
              | Address Block        | 100::/64                   |
              | Name                 | Discard-Only Address Block |
              | RFC                  | [RFC6666]                  |
              | Allocation Date      | June 2012                  |
              | Termination Date     | N/A                        |
              | Source               | True                       |
              | Destination          | True                       |
              | Forwardable          | True                       |
              | Global               | False                      |
              | Reserved-by-Protocol | False                      |
              +----------------------+----------------------------+

                       Table 21: Discard-Only Prefix

              +----------------------+---------------------------+
              | Attribute            | Value                     |
              +----------------------+---------------------------+
              | Address Block        | 2001::/23                 |
              | Name                 | IETF Protocol Assignments |
              | RFC                  | [RFC2928]                 |
              | Allocation Date      | September 2000            |
              | Termination Date     | N/A                       |
              | Source               | False[1]                  |
              | Destination          | False[1]                  |
              | Forwardable          | False[1]                  |
              | Global               | False[1]                  |
              | Reserved-by-Protocol | False                     |
              +----------------------+---------------------------+

             [1] Unless allowed by a more specific allocation.

                    Table 22: IETF Protocol Assignments
















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RFC 6890           Special-Purpose Address Registries         April 2013


                    +----------------------+----------------+
                    | Attribute            | Value          |
                    +----------------------+----------------+
                    | Address Block        | 2001::/32      |
                    | Name                 | TEREDO         |
                    | RFC                  | [RFC4380]      |
                    | Allocation Date      | January 2006   |
                    | Termination Date     | N/A            |
                    | Source               | True           |
                    | Destination          | True           |
                    | Forwardable          | True           |
                    | Global               | False          |
                    | Reserved-by-Protocol | False          |
                    +----------------------+----------------+

                             Table 23: TEREDO

                    +----------------------+----------------+
                    | Attribute            | Value          |
                    +----------------------+----------------+
                    | Address Block        | 2001:2::/48    |
                    | Name                 | Benchmarking   |
                    | RFC                  | [RFC5180]      |
                    | Allocation Date      | April 2008     |
                    | Termination Date     | N/A            |
                    | Source               | True           |
                    | Destination          | True           |
                    | Forwardable          | True           |
                    | Global               | False          |
                    | Reserved-by-Protocol | False          |
                    +----------------------+----------------+

                          Table 24: Benchmarking


















Cotton, et al.            Best Current Practice                [Page 17]

RFC 6890           Special-Purpose Address Registries         April 2013


                    +----------------------+---------------+
                    | Attribute            | Value         |
                    +----------------------+---------------+
                    | Address Block        | 2001:db8::/32 |
                    | Name                 | Documentation |
                    | RFC                  | [RFC3849]     |
                    | Allocation Date      | July 2004     |
                    | Termination Date     | N/A           |
                    | Source               | False         |
                    | Destination          | False         |
                    | Forwardable          | False         |
                    | Global               | False         |
                    | Reserved-by-Protocol | False         |
                    +----------------------+---------------+

                          Table 25: Documentation

                     +----------------------+--------------+
                     | Attribute            | Value        |
                     +----------------------+--------------+
                     | Address Block        | 2001:10::/28 |
                     | Name                 | ORCHID       |
                     | RFC                  | [RFC4843]    |
                     | Allocation Date      | March 2007   |
                     | Termination Date     | March 2014   |
                     | Source               | False        |
                     | Destination          | False        |
                     | Forwardable          | False        |
                     | Global               | False        |
                     | Reserved-by-Protocol | False        |
                     +----------------------+--------------+

                             Table 26: ORCHID


















Cotton, et al.            Best Current Practice                [Page 18]

RFC 6890           Special-Purpose Address Registries         April 2013


                    +----------------------+---------------+
                    | Attribute            | Value         |
                    +----------------------+---------------+
                    | Address Block        | 2002::/16 [2] |
                    | Name                 | 6to4          |
                    | RFC                  | [RFC3056]     |
                    | Allocation Date      | February 2001 |
                    | Termination Date     | N/A           |
                    | Source               | True          |
                    | Destination          | True          |
                    | Forwardable          | True          |
                    | Global               | N/A [2]       |
                    | Reserved-by-Protocol | False         |
                    +----------------------+---------------+

                      [2] See [RFC3056] for details.

                              Table 27: 6to4

                     +----------------------+--------------+
                     | Attribute            | Value        |
                     +----------------------+--------------+
                     | Address Block        | fc00::/7     |
                     | Name                 | Unique-Local |
                     | RFC                  | [RFC4193]    |
                     | Allocation Date      | October 2005 |
                     | Termination Date     | N/A          |
                     | Source               | True         |
                     | Destination          | True         |
                     | Forwardable          | True         |
                     | Global               | False        |
                     | Reserved-by-Protocol | False        |
                     +----------------------+--------------+

                          Table 28: Unique-Local
















Cotton, et al.            Best Current Practice                [Page 19]

RFC 6890           Special-Purpose Address Registries         April 2013


                +----------------------+-----------------------+
                | Attribute            | Value                 |
                +----------------------+-----------------------+
                | Address Block        | fe80::/10             |
                | Name                 | Linked-Scoped Unicast |
                | RFC                  | [RFC4291]             |
                | Allocation Date      | February 2006         |
                | Termination Date     | N/A                   |
                | Source               | True                  |
                | Destination          | True                  |
                | Forwardable          | False                 |
                | Global               | False                 |
                | Reserved-by-Protocol | True                  |
                +----------------------+-----------------------+

                      Table 29: Linked-Scoped Unicast

3.  Security Considerations

   Security of the Internet's routing system relies on the ability to
   authenticate an assertion of unique control of an address block.
   Measures to authenticate such assertions rely on validation that the
   address block forms part of an existing allocated address block and
   that there is a trustable and unique reference in the IANA address
   registries.

   The proposed registry is intended to provide an authoritative source
   of information regarding the currency and intended purpose of special
   purpose address blocks that are designated from the IANA-administered
   Special-Purpose registry.  This is a small step towards the creation
   of a comprehensive registry framework that can be used as a trust
   point for commencing a chain of address validation.  Consideration
   should be given to IANA registry publication formats that are machine
   parsable.  Additionally, consideration should be given to the use of
   file signatures and associated certificate mechanisms to allow
   applications to confirm that the registry contents are current and
   that they have been published by the IANA.

4.  Acknowledgements

   The authors thank Geoff Huston and Randy Bush for their helpful
   comments.  The authors also express their gratitude to an anonymous
   donor, without whom this document would not have been written.

5.  Informative References

   [RFC0919]  Mogul, J., "Broadcasting Internet Datagrams", STD 5, RFC
              919, October 1984.



Cotton, et al.            Best Current Practice                [Page 20]

RFC 6890           Special-Purpose Address Registries         April 2013


   [RFC1112]  Deering, S., "Host extensions for IP multicasting", STD 5,
              RFC 1112, August 1989.

   [RFC1122]  Braden, R., Ed., "Requirements for Internet Hosts -
              Communication Layers", STD 3, RFC 1122, October 1989.

   [RFC1918]  Rekhter, Y., Moskowitz, B., Karrenberg, D., de Groot, G.,
              and E. Lear, "Address Allocation for Private Internets",
              BCP 5, RFC 1918, February 1996.

   [RFC2544]  Bradner, S. and J. McQuaid, "Benchmarking Methodology for
              Network Interconnect Devices", RFC 2544, March 1999.

   [RFC2860]  Carpenter, B., Baker, F., and M. Roberts, "Memorandum of
              Understanding Concerning the Technical Work of the
              Internet Assigned Numbers Authority", RFC 2860, June 2000.

   [RFC2928]  Hinden, R., Deering, S., Fink, R., and T. Hain, "Initial
              IPv6 Sub-TLA ID Assignments", RFC 2928, September 2000.

   [RFC3056]  Carpenter, B. and K. Moore, "Connection of IPv6 Domains
              via IPv4 Clouds", RFC 3056, February 2001.

   [RFC3068]  Huitema, C., "An Anycast Prefix for 6to4 Relay Routers",
              RFC 3068, June 2001.

   [RFC3849]  Huston, G., Lord, A., and P. Smith, "IPv6 Address Prefix
              Reserved for Documentation", RFC 3849, July 2004.

   [RFC3927]  Cheshire, S., Aboba, B., and E. Guttman, "Dynamic
              Configuration of IPv4 Link-Local Addresses", RFC 3927, May
              2005.

   [RFC4193]  Hinden, R. and B. Haberman, "Unique Local IPv6 Unicast
              Addresses", RFC 4193, October 2005.

   [RFC4291]  Hinden, R. and S. Deering, "IP Version 6 Addressing
              Architecture", RFC 4291, February 2006.

   [RFC4379]  Kompella, K. and G. Swallow, "Detecting Multi-Protocol
              Label Switched (MPLS) Data Plane Failures", RFC 4379,
              February 2006.

   [RFC4380]  Huitema, C., "Teredo: Tunneling IPv6 over UDP through
              Network Address Translations (NATs)", RFC 4380, February
              2006.





Cotton, et al.            Best Current Practice                [Page 21]

RFC 6890           Special-Purpose Address Registries         April 2013


   [RFC4773]  Huston, G., "Administration of the IANA Special Purpose
              IPv6 Address Block", RFC 4773, December 2006.

   [RFC4843]  Nikander, P., Laganier, J., and F. Dupont, "An IPv6 Prefix
              for Overlay Routable Cryptographic Hash Identifiers
              (ORCHID)", RFC 4843, April 2007.

   [RFC5156]  Blanchet, M., "Special-Use IPv6 Addresses", RFC 5156,
              April 2008.

   [RFC5180]  Popoviciu, C., Hamza, A., Van de Velde, G., and D.
              Dugatkin, "IPv6 Benchmarking Methodology for Network
              Interconnect Devices", RFC 5180, May 2008.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.

   [RFC5735]  Cotton, M. and L. Vegoda, "Special Use IPv4 Addresses",
              RFC 5735, January 2010.

   [RFC5736]  Huston, G., Cotton, M., and L. Vegoda, "IANA IPv4 Special
              Purpose Address Registry", RFC 5736, January 2010.

   [RFC5737]  Arkko, J., Cotton, M., and L. Vegoda, "IPv4 Address Blocks
              Reserved for Documentation", RFC 5737, January 2010.

   [RFC5884]  Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow,
              "Bidirectional Forwarding Detection (BFD) for MPLS Label
              Switched Paths (LSPs)", RFC 5884, June 2010.

   [RFC6052]  Bao, C., Huitema, C., Bagnulo, M., Boucadair, M., and X.
              Li, "IPv6 Addressing of IPv4/IPv6 Translators", RFC 6052,
              October 2010.

   [RFC6333]  Durand, A., Droms, R., Woodyatt, J., and Y. Lee, "Dual-
              Stack Lite Broadband Deployments Following IPv4
              Exhaustion", RFC 6333, August 2011.

   [RFC6598]  Weil, J., Kuarsingh, V., Donley, C., Liljenstolpe, C., and
              M. Azinger, "IANA-Reserved IPv4 Prefix for Shared Address
              Space", BCP 153, RFC 6598, April 2012.

   [RFC6666]  Hilliard, N. and D. Freedman, "A Discard Prefix for IPv6",
              RFC 6666, August 2012.






Cotton, et al.            Best Current Practice                [Page 22]

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Authors' Addresses

   Michelle Cotton
   Internet Corporation for Assigned Names and Numbers (ICANN)
   12025 Waterfront Drive, Suite 300
   Los Angeles, CA 90094-2536
   USA

   Phone: +310-823-9358
   EMail: michelle.cotton@icann.org
   URI:   http://www.icann.org/


   Leo Vegoda
   Internet Corporation for Assigned Names and Numbers (ICANN)
   12025 Waterfront Drive, Suite 300
   Los Angeles, CA 90094-2536
   USA

   Phone: +310-823-9358
   EMail: leo.vegoda@icann.org
   URI:   http://www.icann.org/


   Ronald P Bonica (editor)
   Juniper Networks
   2251 Corporate Park Drive
   Herndon, VA 20171
   USA

   EMail: rbonica@juniper.net


   Brian Haberman
   Johns Hopkins University (JHU) Applied Physics Lab
   11100 Johns Hopkins Road
   Laurel, MD 20723-6099
   USA

   EMail: brian@innovationslab.net











Cotton, et al.            Best Current Practice                [Page 23]


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