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diff --git a/doc/rfc/rfc7335.txt b/doc/rfc/rfc7335.txt new file mode 100644 index 0000000..a43caf1 --- /dev/null +++ b/doc/rfc/rfc7335.txt @@ -0,0 +1,227 @@ + + + + + + +Internet Engineering Task Force (IETF) C. Byrne +Request for Comments: 7335 T-Mobile US +Updates: 6333 August 2014 +Category: Standards Track +ISSN: 2070-1721 + + + IPv4 Service Continuity Prefix + +Abstract + + Dual-Stack Lite (DS-Lite), defined in RFC 6333, directs IANA to + reserve 192.0.0.0/29 for the Basic Bridging BroadBand (B4) element. + Per this memo, IANA has generalized that reservation to include other + cases where a non-routed IPv4 interface must be numbered as part of + an IPv6 transition solution. + +Status of This Memo + + This is an Internet Standards Track document. + + 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 + Internet Standards 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/rfc7335. + +Copyright Notice + + Copyright (c) 2014 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. + + + + + + +Byrne Standards Track [Page 1] + +RFC 7335 IPv4 Service Continuity Prefix August 2014 + + +Table of Contents + + 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 + 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 2 + 3. The Case of 464XLAT . . . . . . . . . . . . . . . . . . . . . 2 + 4. Choosing 192.0.0.0/29 . . . . . . . . . . . . . . . . . . . . 3 + 5. Security Considerations . . . . . . . . . . . . . . . . . . . 3 + 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3 + 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 4 + 8. Normative References . . . . . . . . . . . . . . . . . . . . . 4 + +1. Introduction + + DS-Lite [RFC6333] directs IANA to reserve 192.0.0.0/29 for the Basic + Bridging BroadBand (B4) element. This memo generalizes that IANA + reservation to include other cases where a non-routed IPv4 interface + must be numbered in an IPv6 transition solution. IANA has listed the + address block 192.0.0.0/29 reserved for IPv4 Service Continuity + Prefix. The result is that 192.0.0.0/29 may be used in any system + that requires IPv4 addresses for backward compatibility with IPv4 + communications in an IPv6-only network but does not emit IPv4 packets + "on the wire". + + This generalization does not impact the use of the IPv4 Service + Continuity Prefix in a DS-Lite context. + +2. Conventions + + 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 [RFC2119]. + +3. The Case of 464XLAT + + 464XLAT [RFC6877] describes an architecture for providing IPv4 + communication over an IPv6-only access network. One of the methods + described in [RFC6877] is for the customer-side translator (CLAT) to + be embedded in the host, such as a smartphone or a CPE (Customer + Premises Equipment). In such scenarios, the host must have an IPv4 + address configured to present to the host network stack and for + applications to bind IPv4 sockets. + + + + + + + + + + +Byrne Standards Track [Page 2] + +RFC 7335 IPv4 Service Continuity Prefix August 2014 + + +4. Choosing 192.0.0.0/29 + + To avoid conflicts with any other network that may communicate with + the CLAT or other IPv6 transition solution, a locally unique IPv4 + address must be assigned. + + IANA has defined a well-known range, 192.0.0.0/29, in [RFC6333], + which is dedicated for DS-Lite. As defined in [RFC6333], this subnet + is only present between the B4 and the Address Family Transition + Router (AFTR) and never emits packets from this prefix "on the wire". + 464XLAT has the same need for a non-routed IPv4 prefix, and this same + need may be common for other similar solutions. It is most prudent + and effective to generalize 192.0.0.0/29 for the use of supporting + IPv4 interfaces in IPv6 transition technologies rather than reserving + a prefix for every possible solution. + + With this memo, 192.0.0.0/29 is now generalized across multiple IPv4 + continuity solutions such as 464XLAT and DS-Lite. A host MUST NOT + enable two active IPv4 continuity solutions simultaneously in a way + that would cause a node to have overlapping 192.0.0.0/29 address + space. + +5. Security Considerations + + There are no new security considerations beyond what is described + [RFC6333] and [RFC6877]. + +6. IANA Considerations + + IANA has updated the IPv4 Special-Purpose Address Registry available + at (http://www.iana.org/assignments/iana-ipv4-special-registry/) as + follows: + + OLD: + + 192.0.0.0/29 DS-Lite [RFC6333] + + NEW: + + 192.0.0.0/29 IPv4 Service Continuity Prefix [RFC7335] + + + + + + + + + + + +Byrne Standards Track [Page 3] + +RFC 7335 IPv4 Service Continuity Prefix August 2014 + + + +----------------------+-----------------------------------+ + | Attribute | Value | + +----------------------+-----------------------------------+ + | Address Block | 192.0.0.0/29 | + | Name | IPv4 Service Continuity Prefix | + | RFC | RFC 7335 | + | Allocation Date | June 2011 | + | Termination Date | N/A | + | Source | True | + | Destination | True | + | Forwardable | True | + | Global | False | + | Reserved-by-Protocol | False | + +----------------------+-----------------------------------+ + +7. Acknowledgements + + This document has been substantially improved by specific feedback + from Dave Thaler, Fred Baker, Wes George, Lorenzo Colitti, and + Mohamed Boucadair. + +8. Normative References + + [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate + Requirement Levels", BCP 14, RFC 2119, March 1997. + + [RFC6333] Durand, A., Droms, R., Woodyatt, J., and Y. Lee, "Dual- + Stack Lite Broadband Deployments Following IPv4 + Exhaustion", RFC 6333, August 2011. + + [RFC6877] Mawatari, M., Kawashima, M., and C. Byrne, "464XLAT: + Combination of Stateful and Stateless Translation", RFC + 6877, April 2013. + +Author's Address + + Cameron Byrne + Bellevue, WA + USA + + EMail: Cameron.Byrne@T-Mobile.com + + + + + + + + + + +Byrne Standards Track [Page 4] + |