RFC 6264
An Incremental Carrier-Grade NAT (CGN) for IPv6 Transition
Abstract
Okay so, the TL;DR is that global IPv6 rollout has been slower than everyone predicted 💅. IPv4 address exhaustion is getting closer, which makes IPv4-to-IPv6 transition issues more urgent and way harder to handle 😭. Host-based transition mechanisms, the kind used in dual-stack setups, can't cover every transition requirement. And most end users aren't expert enough to configure or maintain those host-based mechanisms 🙈. Carrier-Grade NAT (CGN) devices with transition mechanisms built in can cut down on the operational changes needed during the IPv4-to-IPv6 migration or coexistence period ✨.
The big idea here is an incremental CGN approach for IPv6 transition 🦋. It gives IPv6 access to IPv6 hosts and IPv4 access to IPv4 hosts, while leaving most of a legacy ISP network untouched during the early stage of the migration 🌸. The unlike CGN alone part is what makes it iconic: it also supports and encourages a smooth move toward dual-stack or IPv6-only ISP networks 👑. The doc describes an integrated, configurable CGN device and an adaptive home gateway (HG) device. Both can be reused across different transition phases, so nobody has to upgrade over and over 💜. Basically, IPv6 migration happens step by step, based on what real users actually need 🎀.
Status of This Memo
Let's get the paperwork out of the way 🍓. This document is not an Internet Standards Track specification. It's published for informational purposes only ✨.
It's a product of the Internet Engineering Task Force (IETF), so it reflects the consensus of the IETF community. It got public review and was approved for publication by the Internet Engineering Steering Group (IESG) 💖. Not every IESG-approved document is a candidate for any level of Internet Standard, so check Section 2 of RFC 5741 if you're curious 🧐.
Want the current status, any errata, or a way to send feedback? Head to http://www.rfc-editor.org/info/rfc6264 🌈.
Copyright Notice
Copyright (c) 2011 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, which you can find at http://trustee.ietf.org/license-info as they stood on the publication date ⚖️. Please actually read those, because they spell out your rights and restrictions for this document 🫶. Any Code Components pulled out of this document must include Simplified BSD License text, as described in Section 4.e of the Trust Legal Provisions, and they come without warranty, just like the Simplified BSD License says 💅.
Table of Contents
1. Introduction ....................................................2
2. An Incremental CGN Approach .....................................4
2.1. Incremental CGN Approach Overview ..........................4
2.2. Choice of Tunneling Technology .............................5
2.3. Behavior of Dual-Stack Home Gateway ........................6
2.4. Behavior of Dual-Stack CGN .................................6
2.5. Impact for Existing Hosts and Unchanged Networks ...........7
2.6. IPv4/IPv6 Intercommunication ...............................7
2.7. Discussion .................................................8
3. Smooth Transition towards IPv6 Infrastructure ...................8
4. Security Considerations ........................................10
5. Acknowledgements ...............................................10
6. References .....................................................10
6.1. Normative References ......................................10
6.2. Informative References ....................................111. Introduction ✨
Okay, so global IPv6 deployment did not go the way everyone forecast 10 years ago 😭. Network providers were hesitant to make the first move, because IPv4 was and still is working really well 💅. But IPv4 address exhaustion is imminent 🔥. The dynamically updated IPv4 Address Report [IPUSAGE] has been tracking this. IANA's unallocated address pool ran out in February 2011, and at publication time, the site predicted that the Regional Internet Registry (RIR) unallocated address pools were about to run out too 🌸. So the Internet industry seems to have reached consensus that global IPv6 deployment is inevitable and has to happen expeditiously 🦋.
That means IPv4-to-IPv6 transition issues get more critical and complicated as global IPv6 deployment approaches 😩. Host-based transition mechanisms alone can't meet the requirements in every case 🙈. So we need network-based supporting functions and/or new transition mechanisms that keep the user-side operation simple 🫶.
Carrier-Grade NAT (CGN) [CGN-REQS], also called NAT444 CGN or Large Scale NAT, makes IPv4 operational problems worse when it's used alone, and it does nothing to encourage IPv4-to-IPv6 transition 💀. Deploying NAT444 CGN lets ISPs put off the transition, which causes double transition costs: once to add the CGN, and again to support IPv6 🍓.
CGN deployments that integrate multiple transition mechanisms can simplify end-user services during the IPv4-to-IPv6 migration and coexistence periods ✨. CGNs live on the network side and are managed and maintained by professionals 💅. On the user side, new home gateway (HG) devices may be needed too 🏠. Network providers may supply them, depending on the business model 💜. Dual-stack lite [DS-LITE], also called DS-Lite, is a CGN-based solution that supports transition, but it requires the ISP to upgrade its network to IPv6 immediately 😬. Plenty of ISPs hesitate to do that as step one 🙈. Theoretically, DS-Lite can be used with double encapsulation (IPv4-in-IPv6-in-IPv4), but that seems even less likely to fly with an ISP, and this document doesn't discuss it 🧐.
Now the good stuff ✨. This document proposes an incremental CGN approach for IPv6 transition 🦋. It doesn't define any new protocols or mechanisms. Instead, it describes how to combine existing proposals for incremental deployment 🎀. It's similar to DS-Lite, but the other way around 🔄. It mainly combines v4-v4 NAT with v6-over-v4 tunneling functions 💖. It can provide IPv6 access services for IPv6-enabled hosts and IPv4 access services for IPv4 hosts, while leaving most of the legacy IPv4 ISP network unchanged 🌈. Legacy IPv4 hosts with global IPv4 addresses aren't affected by this deployment at all 👑. It's a good fit for the initial stage of the IPv4-to-IPv6 migration, and it also supports a transition toward dual-stack or IPv6-only ISP networks ⭐.
There's also a smooth transition mechanism in this document 🦋. It introduces an integrated configurable CGN device and an adaptive HG device. Both the CGN and the HG are reusable across different transition periods, so they don't need to be replaced as the transition moves along 🫶. IPv6 migration can happen incrementally, based on real user requirements 💜.
2. An Incremental CGN Approach 🌸
Today, most consumers mainly use IPv4 📱. Network providers are starting to offer IPv6 access services to end users 🌱. In the early stage of the migration, IPv4 connectivity and traffic will keep making up most of the traffic for most ISP networks 📈. ISPs want to minimize changes to their IPv4 networks 🙏. Switching the whole ISP network to IPv6-only would be a radical move 😳. Switching the whole ISP network to dual-stack is less radical, but it brings operational costs and complications 💅. Some ISPs have successfully deployed dual-stack networks, but others would rather not make that their first step into IPv6 🤷♀️.
Here's the drama 🔥: ISPs face two urgent pressures. One is compensating for an immediate shortage of IPv4 addresses by deploying some method of address sharing. The other is preparing actively for the use of IPv6 address space and services 💖. ISPs facing only one of the two pressures could adopt either CGN (for the IPv4 address shortage) or 6rd (to provide IPv6 connectivity services) 🎀. The approach in this document is meant to address both pressures at the same time, by combining v4-v4 CGN with v6-over-v4 tunneling technologies 👑.
2.1. Incremental CGN Approach Overview ✨
Here's the incremental CGN approach we're proposing, illustrated in the figure below 🦋.
+-------------+
|IPv6 Internet|
+-------------+
|
+---------------+----------+
+-----+ +--+ | IPv4 ISP +--+--+ | +--------+
|v4/v6|---|DS|=======+============| CGN |-------+---| IPv4 |
|Host | |HG| | Network +-----+ | | |Internet|
+-----+ +--+ +----------------------+---+ +--------+
_ _ _ _ _ _ _ _ _ _ _ |
()_6_over_4_ _t_u_n_n_e_l_() +---------------------+
| Existing IPv4 hosts |
+---------------------+Figure 1: Incremental CGN Approach with IPv4 ISP Network
DS HG = Dual-Stack Home Gateway (CPE - Customer Premises Equipment).
As the figure shows, the ISP hasn't significantly changed its IPv4 network 🌈. This approach lets IPv4 hosts reach the IPv4 Internet, and IPv6 hosts reach the IPv6 Internet 💜. A dual-stack host is treated as an IPv4 host when it uses IPv4 access service, and as an IPv6 host when it uses IPv6 access service 🔄. To let IPv4 hosts reach the IPv6 Internet and IPv6 hosts reach the IPv4 Internet, NAT64 can be integrated with the CGN. Check out Section 2.6 for the details on IPv4/IPv6 intercommunication 🧚. The integration of those mechanisms is out of scope for this document 🙅♀️.
Two types of devices need to be deployed in this approach: a dual-stack home gateway (HG) and a dual-stack CGN 🎀. The dual-stack home gateway combines IPv6 and IPv4 forwarding with v6-over-v4 tunneling functions 🏠. It should follow the requirements of [RFC6204], including IPv6 prefix delegation. It may also integrate v4-v4 NAT functionality 🌷. The dual-stack CGN integrates v6-over-v4 tunneling and v4-v4 CGN functions, along with standard IPv6 and IPv4 routing 🛰️.
The approach doesn't need any new mechanisms for IP packet forwarding, or for encapsulation and decapsulation at tunnel endpoints 🙌. The following sections describe how the HG and the incremental CGN interact 🫶.
2.2. Choice of Tunneling Technology 🎀
okay so in theory this model works with any tunnel between the dual-stack HG and the dual-stack CGN 💅 but tunnels that need someone to configure each one by hand are giving operational cost nightmare 😭 so configured tunnels based directly on [RFC4213] are a no-go. a tunnel broker according to [RFC3053] would also have high operational costs and is unsuitable for home users 🙈
6rd [RFC5569, RFC5969] technology looks super suitable for v6-over-v4 tunneling with low operational cost ✨ Generic Routing Encapsulation (GRE) [RFC2784] plus an extra auto-configuration mechanism can also do v6-over-v4 tunneling 🦋 other options like 6over4 [RFC2529], 6to4 [RFC3056], the Intra-Site Automatic Tunnel Addressing Protocol (ISATAP) [RFC5214], or Virtual Enterprise Traversal (VET) [RFC5558] could be considered too 🌸
and if the ISP has a totally MPLS infrastructure between the HG and the dual-stack CGN, it's also possible to use an IPv6 Provider Edge (6PE) [RFC4798] tunnel directly over MPLS 👑 but this would only be suitable for an advanced HG, which is unlikely to be found as a consumer device, so we're not going deeper on it here 💀 to keep things simple, we assume the use of 6rd 💖
2.3. Behavior of Dual-Stack Home Gateway 🧚
okay the dual-stack home gateway gets a data packet from a host and the first thing it does is check whether it's an IPv4 or an IPv6 packet 👀 then the packet gets handed to the IPv4 or IPv6 stack, whichever fits 🫶
for IPv4, if there's no v4-v4 NAT on the HG, the stack just forwards the packet to the CGN, which is normally the IPv4 default router 🍓 but if v4-v4 NAT is turned on, the HG rewrites the packet source address from an HG-scope private IPv4 address into a CGN-scope IPv4 address, does port mapping if it's needed, and then forwards the packet toward the CGN ✨ the HG also records the v4-v4 address and port mapping info for inbound packets, just like any other NAT would 💅
for IPv6, the HG has to wrap the data up inside an IPv4 tunnel packet whose IPv4 destination is the dual-stack CGN 🎀 then it sends that new IPv4 packet toward the CGN, for example using 6rd 🌈
if the HG is linked to more than one CGN, it records the mapping info between the tunnel and the source IPv6 address for inbound packets 🔥 detailed considerations for using multiple CGNs with one HG are for further study 🙈
and finally, IPv4 packets coming from the CGN and encapsulated IPv6 packets coming from the CGN get translated or decapsulated based on the stored mapping info, then forwarded to the customer side of the HG 🦋
2.4. Behavior of Dual-Stack CGN 👑
when a dual-stack CGN gets an IPv4 data packet from a dual-stack home gateway, it figures out whether the packet is a normal, non-encapsulated IPv4 packet, or a v6-over-v4 tunnel packet addressed to a tunnel endpoint inside the CGN 👀 for a normal IPv4 packet, the CGN translates the source address from a CGN-scope IPv4 address into a public IPv4 address, does port mapping if necessary, and forwards it normally to the IPv4 Internet ✨ it records the v4-v4 address and port mapping info for inbound packets, just like a normal NAT does 💖
for a v6-over-v4 tunnel packet, the tunnel endpoint inside the CGN decapsulates it back into the original IPv6 packet and forwards it to the IPv6 Internet 🌸 the CGN also records the mapping info between the tunnel and the source IPv6 address for inbound packets 🫶
depending on where the CGN is deployed, it may use another v6-over-v4 tunnel to connect to the IPv6 Internet 🌈
and on the way back: packets from the IPv4 Internet get properly translated by the CGN and forwarded to the HG, and packets from the IPv6 Internet get tunneled to the right HG, using the stored mapping info as needed 💅✨
2.5. Impact for Existing Hosts and Unchanged Networks 🌸
this approach doesn't touch the unchanged parts of ISP networks at all 🙌 legacy IPv4 ISP networks and their IPv4 devices stay in use, no drama 💜
the existing IPv4 hosts (the lower right box in Figure 1) can connect to the IPv4 Internet just like they do now, whether they have global IPv4 addresses or sit behind v4-v4 NAT 🦋 and if those hosts get upgraded to dual-stack hosts, they can reach the IPv6 Internet through the IPv4 ISP network using IPv6-over-IPv4 tunnel technologies 🔥 (see Section 2.7 for a comment on MTU size 🎀)
2.6. IPv4/IPv6 Intercommunication 🌍
okay real talk, for obvious commercial reasons, IPv6-only public services aren't expected to show up as long as there's a big IPv4-only customer base out there 😭 but IPv4/IPv6 intercommunication may become a real issue in lots of scenarios 💀
the IETF is expected to standardize a recommended IPv4/IPv6 translation algorithm, sometimes called NAT64 ✨ it's specified in the following:
- "Framework for IPv4/IPv6 Translation" [RFC6144]
- "IPv6 Addressing of IPv4/IPv6 Translators" [RFC6052]
- "DNS64: DNS Extensions for Network Address Translation from IPv6 Clients to IPv4 Servers" [RFC6147]
- "IP/ICMP Translation Algorithm" [RFC6145]
- "Stateful NAT64: Network Address and Protocol Translation from IPv6 Clients to IPv4 Servers" [RFC6146]
- "An FTP ALG for IPv6-to-IPv4 Translation" [FTP-ALG]
the service, as described in the IETF's "Guidelines for Using IPv6 Transition Mechanisms during IPv6 Deployment" [RFC6180], gives you stateless translation between hosts in an IPv4-only domain (or hosts offering an IPv4-only service) and hosts with an IPv4-embedded IPv6 address in an IPv6-only domain 💖 it also gives access from IPv6 hosts with general format addresses to hosts in an IPv4-only domain or hosts offering an IPv4-only service 🫶 it does not provide any-to-any translation 🙈 so one result is that client-only hosts in the IPv6 domain can reach IPv4 services through stateful translation 🌸 another result is that the IPv6 network operator can move servers into the IPv6-only domain and still keep them accessible to IPv4-only clients, through stateless translation of an IPv4-embedded IPv6 address 👑
also, "Architectural Implications of NAT" [RFC2993] applies across this service just like it does for IPv4/IPv4 translation 🧚 the difference is that a system with an IPv4-embedded IPv6 address is reachable across the NAT, which is unlike IPv4 😱 and any assumption by an application that a local address means something to a remote peer, or any use of an IP address literal in the application payload, is a source of service issues 🙈 the general mitigation for this is:
- Ideally, applications should use DNS names rather than IP address literals in URLs, URIs, and referrals, and in general be network layer agnostic.
- If they don't, the network may provide a relay or proxy that straddles the domains. For example, an SMTP Mail Transfer Agent (MTA) with both IPv4 and IPv6 connectivity handles IPv4/IPv6 translation cleanly at the application layer ✨
2.7. Discussion 💬
for IPv4 traffic, the incremental CGN approach inherits all the problems of CGN address-sharing techniques [ADDR-ISSUES] (like scaling, and the difficulty of supporting well-known ports for inbound traffic) 😩 application-layer problems created by double NAT are beyond the scope of this document 🙈
for IPv6 traffic, a user behind the DS HG sees normal IPv6 service 🥰 we observe that an IPv6 tunnel MTU of at least 1500 bytes would make sure the mechanism doesn't cause excessive fragmentation of IPv6 traffic or excessive IPv6 path MTU discovery interactions 🔥 this, plus the absence of NAT problems for IPv6, will create an incentive for users and application service providers to prefer IPv6 👑💜
ICMP filtering [RFC4890] may be included as part of CGN functions 🛡️
3. Smooth Transition towards IPv6 Infrastructure ✨
transitioning from pure NAT444 CGN or 6rd to the incremental CGN approach is super straightforward 🦋 the HG and CGN devices and their locations don't have to change; only software upgrading may be needed 💅 in the ideal model (described below), even the software upgrading isn't necessary, and reconfiguring the devices is enough 🎀 NAT444 CGN solves the public address shortage in the current IPv4 infrastructure, but it doesn't contribute to IPv6 deployment at all 😭 the incremental CGN approach can inherit NAT444 CGN functions while providing overlay IPv6 services 🌈 6rd mechanisms can also transform smoothly into this incremental CGN model 🧚 however, the home gateways need to be upgraded correspondingly to perform the steps described below 🫶
the incremental CGN can also easily be moved to an IPv6-enabled infrastructure, where the ISP network is either dual-stack or IPv6-only 🌸
if the ISP prefers to move to dual-stack routing, the HG should simply switch off its v6-over-v4 function when it observes native IPv6 Router Advertisement (RA) or DHCPv6 traffic 🙌 then it forwards both IPv6 and IPv4 traffic directly, while the dual-stack CGN keeps only its v4-v4 NAT function 💖
however, we expect ISPs to choose the incremental CGN approach described here, because they want to avoid dual-stack routing and move incrementally from IPv4-only routing to IPv6-only routing 👑 in this case, the ideal model is an integrated configurable CGN device paired with an adaptive HG device 🔥 the integrated CGN device can support multiple functions, including NAT444 CGN, a 6rd router (or an alternative tunneling mechanism), DS-Lite, and dual-stack forwarding 🦋
the HG has to integrate the corresponding functions and be able to detect relevant incremental changes on the CGN side 👀 typically, the HG will occasionally poll the CGN to discover which features are operational 🫶 for example, starting from a pure IPv4-only scenario (where the HG treats the CGN only as an IPv4 default router), the HG would discover (through infrequent polling) when 6rd became available 🌸 the home user would then acquire an IPv6 prefix 💜 at a later stage, the HG would observe native IPv6 Route Advertisement messages or DHCPv6 messages to discover that an IPv6 service, including DS-Lite, is available 🧚 so when an ISP decides to switch from incremental CGN to DS-Lite CGN, only a configuration change or a minor software update is needed on the CGNs ✨ the home gateway would detect the change and switch automatically to DS-Lite mode 🙌 the only impact on the home user is receiving a different IPv6 prefix 🎀
in the smooth transition model, both the CGN and the HG are reusable devices across the different transition periods 💅 this avoids potential multiple upgrades 🌈 different regions of the same ISP network may be at different stages of the incremental process, using identical equipment but with different configurations of the incremental CGN devices in each region 🫶 so IPv6 migration can be achieved incrementally, according to the real ISP and customer requirements 💖✨
4. Security Considerations ✨
okay bestie, security time 🔒 NAT security issues were already documented in [RFC2663] and [RFC2993] 💅. Security issues for large-scale address sharing, including CGN, are discussed in [ADDR-ISSUES]. This spec doesn't add any new features to CGN itself, so it brings no new security considerations 🫶. 6rd's security issues are documented in [RFC5569] and [RFC5969], and DS-Lite's are discussed in [DS-LITE] 🌸.
Okay, so the tunnels here live entirely inside a single ISP network, between the HG/CPE and the CGN 🦋. That means the threat model is pretty simple, lowkey a vibe ✨. [RFC4891] explains how to protect tunnels with IPsec, but an ISP could reasonably decide its infrastructure is secure enough without the extra protection and overhead of IPsec 🙈. The intrinsic risks of tunnels are covered in [RFC6169], which recommends that tunneled traffic should not cross border routers. The incremental CGN approach respects this recommendation, which is so iconic 👑.
Now, to dodge other tunnel risks, it's really important that any security mechanisms based on packet inspection, plus any ingress filtering, get applied to IPv6 packets after the CGN has decapsulated them 💀. The dual-stack home gateway will also need to provide basic security functionality for IPv6 [RFC6092] 🎀. Other aspects are described in [RFC4864] 💜.
5. Acknowledgements
Big thank-yous to Fred Baker, Dan Wing, Fred Templin, Seiichi Kawamura, Remi Despres, Janos Mohacsi, Mohamed Boucadair, Shin Miyakawa, Joel Jaeggli, Jari Arkko, Tim Polk, Sean Turner, and the rest of the IETF V6OPS working group 🫶🌈. They gave useful comments, and this doc is better because of them ✨.
6. References
6.1. Normative References
- [RFC2529] Carpenter, B. and C. Jung, "Transmission of IPv6 over IPv4 Domains without Explicit Tunnels", RFC 2529, March 1999.
- [RFC2784] Farinacci, D., Li, T., Hanks, S., Meyer, D., and P. Traina, "Generic Routing Encapsulation (GRE)", RFC 2784, March 2000.
- [RFC5569] Despres, R., "IPv6 Rapid Deployment on IPv4 Infrastructures (6rd)", RFC 5569, January 2010.
- [RFC5969] Townsley, W. and O. Troan, "IPv6 Rapid Deployment on IPv4 Infrastructures (6rd) -- Protocol Specification", RFC 5969, August 2010.
6.2. Informative References
- [RFC2663] Srisuresh, P. and M. Holdrege, "IP Network Address Translator (NAT) Terminology and Considerations", RFC 2663, August 1999.
- [RFC2993] Hain, T., "Architectural Implications of NAT", RFC 2993, November 2000.
- [RFC3053] Durand, A., Fasano, P., Guardini, I., and D. Lento, "IPv6 Tunnel Broker", RFC 3053, January 2001.
- [RFC3056] Carpenter, B. and K. Moore, "Connection of IPv6 Domains via IPv4 Clouds", RFC 3056, February 2001.
- [RFC4213] Nordmark, E. and R. Gilligan, "Basic Transition Mechanisms for IPv6 Hosts and Routers", RFC 4213, October 2005.
- [RFC4798] De Clercq, J., Ooms, D., Prevost, S., and F. Le Faucheur, "Connecting IPv6 Islands over IPv4 MPLS Using IPv6 Provider Edge Routers (6PE)", RFC 4798, February 2007.
- [RFC4864] Van de Velde, G., Hain, T., Droms, R., Carpenter, B., and E. Klein, "Local Network Protection for IPv6", RFC 4864, May 2007.
- [RFC4890] Davies, E. and J. Mohacsi, "Recommendations for Filtering ICMPv6 Messages in Firewalls", RFC 4890, May 2007.
- [RFC4891] Graveman, R., Parthasarathy, M., Savola, P., and H. Tschofenig, "Using IPsec to Secure IPv6-in-IPv4 Tunnels", RFC 4891, May 2007.
- [RFC5214] Templin, F., Gleeson, T., and D. Thaler, "Intra-Site Automatic Tunnel Addressing Protocol (ISATAP)", RFC 5214, March 2008.
- [RFC5558] Templin, F., Ed., "Virtual Enterprise Traversal (VET)", RFC 5558, February 2010.
- [RFC6052] Bao, C., Huitema, C., Bagnulo, M., Boucadair, M., and X. Li, "IPv6 Addressing of IPv4/IPv6 Translators", RFC 6052, October 2010.
- [RFC6092] Woodyatt, J., Ed., "Recommended Simple Security Capabilities in Customer Premises Equipment (CPE) for Providing Residential IPv6 Internet Service", RFC 6092, January 2011.
- [RFC6144] Baker, F., Li, X., Bao, C., and K. Yin, "Framework for IPv4/IPv6 Translation", RFC 6144, April 2011.
- [RFC6145] Li, X., Bao, C., and F. Baker, "IP/ICMP Translation Algorithm", RFC 6145, April 2011.
- [RFC6146] Bagnulo, M., Matthews, P., and I. van Beijnum, "Stateful NAT64: Network Address and Protocol Translation from IPv6 Clients to IPv4 Servers", RFC 6146, April 2011.
- [RFC6147] Bagnulo, M., Sullivan, A., Matthews, P., and I. van Beijnum, "DNS64: DNS Extensions for Network Address Translation from IPv6 Clients to IPv4 Servers", RFC 6147, April 2011.
- [RFC6169] Krishnan, S., Thaler, D., and J. Hoagland, "Security Concerns with IP Tunneling", RFC 6169, April 2011.
- [RFC6180] Arkko, J. and F. Baker, "Guidelines for Using IPv6 Transition Mechanisms during IPv6 Deployment", RFC 6180, May 2011.
- [RFC6204] Singh, H., Beebee, W., Donley, C., Stark, B., and O. Troan, Ed., "Basic Requirements for IPv6 Customer Edge Routers", RFC 6204, April 2011.
- [IPUSAGE] G. Huston, IPv4 Address Report, June 2011,
http://www.potaroo.net/tools/ipv4/index.html. - [DS-LITE] Durand, A., Droms, R., Woodyatt, J., and Y. Lee, "Dual-Stack Lite Broadband Deployments Following IPv4 Exhaustion", Work in Progress, May 2011.
- [ADDR-ISSUES] Ford, M., Boucadair, M., Durand, A., Levis, P., and P. Roberts, "Issues with IP Address Sharing", Work in Progress, March 2011.
- [CGN-REQS] Perreault, S., Ed., Yamagata, I., Miyakawa, S., Nakagawa, A., and H. Ashida, "Common requirements for IP address sharing schemes", Work in Progress, March 2011.
- [FTP-ALG] van Beijnum, I., "An FTP ALG for IPv6-to-IPv4 Translation", Work in Progress, May 2011.
Authors' Addresses
Sheng Jiang
Huawei Technologies Co., Ltd
Huawei Building, No.3 Xinxi Rd.,
Shang-Di Information Industry Base, Hai-Dian District
Beijing 100085
P.R. China
EMail: jiangsheng@huawei.com
Dayong Guo
Huawei Technologies Co., Ltd
Huawei Building, No.3 Xinxi Rd.,
Shang-Di Information Industry Base, Hai-Dian District
Beijing 100085
P.R. China
EMail: guoseu@huawei.com
Brian Carpenter
Department of Computer Science
University of Auckland
PB 92019
Auckland, 1142
New Zealand
EMail: brian.e.carpenter@gmail.com📦 where this page comes from
- ietf: rfc6264 2011-06
- 💖 girlified by claude-haiku-5-5 on : a language model's rewrite of the original, under its terms