draft-ietf-v6ops-464xlat-08.txt   draft-ietf-v6ops-464xlat-09.txt 
Internet Engineering Task Force M. Mawatari Internet Engineering Task Force M. Mawatari
Internet-Draft Japan Internet Exchange Co.,Ltd. Internet-Draft Japan Internet Exchange Co.,Ltd.
Intended status: BCP M. Kawashima Intended status: BCP M. Kawashima
Expires: March 22, 2013 NEC AccessTechnica, Ltd. Expires: July 26, 2013 NEC AccessTechnica, Ltd.
C. Byrne C. Byrne
T-Mobile USA T-Mobile USA
September 18, 2012 January 22, 2013
464XLAT: Combination of Stateful and Stateless Translation 464XLAT: Combination of Stateful and Stateless Translation
draft-ietf-v6ops-464xlat-08 draft-ietf-v6ops-464xlat-09
Abstract Abstract
This document describes an architecture (464XLAT) for providing This document describes an architecture (464XLAT) for providing
limited IPv4 connectivity across an IPv6-only network by combining limited IPv4 connectivity across an IPv6-only network by combining
existing and well-known stateful protocol translation RFC 6146 in the existing and well-known stateful protocol translation RFC 6146 in the
core and stateless protocol translation RFC 6145 at the edge. 464XLAT core and stateless protocol translation RFC 6145 at the edge. 464XLAT
is a simple and scalable technique to quickly deploy limited IPv4 is a simple and scalable technique to quickly deploy limited IPv4
access service to IPv6-only edge networks without encapsulation. access service to IPv6-only edge networks without encapsulation.
skipping to change at page 1, line 38 skipping to change at page 1, line 38
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Copyright Notice Copyright Notice
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. BCP Scenario . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. BCP Scenario . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Requirements Language . . . . . . . . . . . . . . . . . . . . 3 3. Requirements Language . . . . . . . . . . . . . . . . . . . . 4
4. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
5. Motivation and Uniqueness of 464XLAT . . . . . . . . . . . . . 4 5. Motivation and Uniqueness of 464XLAT . . . . . . . . . . . . . 4
6. Network Architecture . . . . . . . . . . . . . . . . . . . . . 4 6. Network Architecture . . . . . . . . . . . . . . . . . . . . . 5
6.1. Wireline Network Architecture . . . . . . . . . . . . . . 4 6.1. Wireline Network Architecture . . . . . . . . . . . . . . 5
6.2. Wireless 3GPP Network Architecture . . . . . . . . . . . . 5 6.2. Wireless 3GPP Network Architecture . . . . . . . . . . . . 6
7. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 6 7. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 7
7.1. Wireline Network Applicability . . . . . . . . . . . . . . 6 7.1. Wireline Network Applicability . . . . . . . . . . . . . . 7
7.2. Wireless 3GPP Network Applicability . . . . . . . . . . . 7 7.2. Wireless 3GPP Network Applicability . . . . . . . . . . . 8
8. Implementation Considerations . . . . . . . . . . . . . . . . 7 8. Implementation Considerations . . . . . . . . . . . . . . . . 8
8.1. IPv6 Address Format . . . . . . . . . . . . . . . . . . . 7 8.1. IPv6 Address Format . . . . . . . . . . . . . . . . . . . 8
8.2. IPv4/IPv6 Address Translation Chart . . . . . . . . . . . 7 8.2. IPv4/IPv6 Address Translation Chart . . . . . . . . . . . 8
8.3. IPv6 Prefix Handling . . . . . . . . . . . . . . . . . . . 9 8.3. IPv6 Prefix Handling . . . . . . . . . . . . . . . . . . . 10
8.4. DNS Proxy Implementation . . . . . . . . . . . . . . . . . 9 8.4. DNS Proxy Implementation . . . . . . . . . . . . . . . . . 10
8.5. CLAT in a Gateway . . . . . . . . . . . . . . . . . . . . 9 8.5. CLAT in a Gateway . . . . . . . . . . . . . . . . . . . . 10
8.6. CLAT to CLAT communications . . . . . . . . . . . . . . . 9 8.6. CLAT to CLAT communications . . . . . . . . . . . . . . . 10
9. Deployment Considerations . . . . . . . . . . . . . . . . . . 9 9. Deployment Considerations . . . . . . . . . . . . . . . . . . 11
9.1. Traffic Engineering . . . . . . . . . . . . . . . . . . . 10 9.1. Traffic Engineering . . . . . . . . . . . . . . . . . . . 11
9.2. Traffic Treatment Scenarios . . . . . . . . . . . . . . . 10 9.2. Traffic Treatment Scenarios . . . . . . . . . . . . . . . 11
10. Security Considerations . . . . . . . . . . . . . . . . . . . 11 10. Security Considerations . . . . . . . . . . . . . . . . . . . 12
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 11 12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12
13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 11 13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13
13.1. Normative References . . . . . . . . . . . . . . . . . . . 11 13.1. Normative References . . . . . . . . . . . . . . . . . . . 13
13.2. Informative References . . . . . . . . . . . . . . . . . . 12 13.2. Informative References . . . . . . . . . . . . . . . . . . 13
Appendix A. Examples of IPv4/IPv6 Address Translation . . . . . . 12 Appendix A. Examples of IPv4/IPv6 Address Translation . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction 1. Introduction
With the exhaustion of the unallocated IPv4 address pools, it will be With the exhaustion of the unallocated IPv4 address pools, it will be
difficult for many networks to assign IPv4 addresses to end users. difficult for many networks to assign IPv4 addresses to end users.
This document describes an IPv4 over IPv6 solution as one of the This document describes an IPv4 over IPv6 solution as one of the
techniques for IPv4 service extension and encouragement of IPv6 techniques for IPv4 service extension and encouragement of IPv6
deployment. 464XLAT is not a one-for-one replacement of full IPv4 deployment. 464XLAT is not a one-for-one replacement of full IPv4
functionality. The 464XLAT architecture only supports IPv4 in the functionality. The 464XLAT architecture only supports IPv4 in the
client server model, where the server has a global IPv4 address. client server model, where the server has a global IPv4 address.
This means it is not fit for IPv4 peer-to-peer communication or This means it is not fit for IPv4 peer-to-peer communication or
inbound IPv4 connections. 464XLAT builds on IPv6 transport and inbound IPv4 connections. 464XLAT builds on IPv6 transport and
includes full any-to-any IPv6 communication. includes full any-to-any IPv6 communication.
The 464XLAT architecture described in this document uses IPv4/IPv6 The 464XLAT architecture described in this document uses IPv4/IPv6
translation standardized in [RFC6145] and [RFC6146]. It does not translation standardized in [RFC6145] and [RFC6146]. It does not
require DNS64 [RFC6147] since an IPv4 host may simply send IPv4 require DNS64 [RFC6147] since an IPv4 host may simply send IPv4
packets, including packets to an IPv4 DNS server, which will be packets, including packets to an IPv4 DNS server, which will be
translated on the customer side translator(CLAT) to IPv6 and back to translated on the customer side translator (CLAT) to IPv6 and back to
IPv4 on the provider side translator(PLAT). 464XLAT networks may use IPv4 on the provider side translator (PLAT). 464XLAT networks may use
DNS64 [RFC6147] to enable single stateful translation [RFC6146] DNS64 [RFC6147] to enable single stateful translation [RFC6146]
instead of 464XLAT double translation where possible. The 464XLAT instead of 464XLAT double translation where possible. The 464XLAT
architecture encourages the IPv6 transition by making IPv4 services architecture encourages the IPv6 transition by making IPv4 services
reachable across IPv6-only networks and providing IPv6 and IPv4 reachable across IPv6-only networks and providing IPv6 and IPv4
connectivity to single-stack IPv4 or IPv6 servers and peers. connectivity to single-stack IPv4 or IPv6 servers and peers.
2. BCP Scenario 2. BCP Scenario
This BCP only applies when the following two criteria are present: This document describes one way to deploy an IPv6-only access
network, built on a 464XLAT architecture. Likely motivations for
running an IPv6-only access network include the fact that IPv6-only
single protocol operation is less complex and IPv4 addresses are
scarce. Providing an IPv6-only network involves either tunneling or
translation. This document describes how to build one type of
solution based on translation. What is described herein has been
implemented and shown to work well, and is the best current practice
for building a service based on 464XLAT architecture.
This BCP only applies when the following three criteria are present:
1. There is an IPv6-only network that uses stateful translation 1. There is an IPv6-only network that uses stateful translation
[RFC6146] as the only mechanism for providing IPv4 access. [RFC6146] as the only mechanism for providing IPv4 access.
2. There are IPv4-only applications or hosts that must communicate 2. There are IPv4-only applications or hosts that must communicate
across the IPv6-only network to reach the IPv4 Internet. across the IPv6-only network to reach the IPv4 Internet.
3. Existing business or technical artifacts preclude the use of a
tunnel based IPv6 transition mechanism.
3. Requirements Language 3. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
4. Terminology 4. Terminology
PLAT: PLAT is Provider side translator(XLAT) that complies with PLAT: PLAT is Provider side translator(XLAT) that complies with
[RFC6146]. It translates N:1 global IPv6 addresses to global [RFC6146]. It translates N:1 global IPv6 addresses to global
IPv4 addresses, and vice versa. IPv4 addresses, and vice versa.
CLAT: CLAT is Customer side translator(XLAT) that complies with CLAT: CLAT is Customer side translator(XLAT) that complies with
[RFC6145]. It algorithmically translates 1:1 private IPv4 [RFC6145]. It algorithmically translates 1:1 private IPv4
addresses to global IPv6 addresses, and vice versa. The CLAT addresses to global IPv6 addresses, and vice versa. The CLAT
function is applicable to a router or an end-node such as a function is applicable to a router or an end-node such as a
mobile phone. The CLAT SHOULD perform router function to mobile phone. The CLAT SHOULD perform IP routing and
facilitate packets forwarding through the stateless forwarding to facilitate packets forwarding through the
translation even if it is an end-node. The CLAT as a common stateless translation even if it is an end-node. The CLAT as
home router or wireless 3GPP router is expected to perform a common home router or wireless Third Generation Partnership
gateway functions such as DHCP server and DNS proxy for local Project (3GPP) router is expected to perform gateway
clients. The CLAT does not comply with the sentence "Both functions such as DHCP server and DNS proxy for local
IPv4-translatable IPv6 addresses and IPv4-converted IPv6 clients. The CLAT uses different IPv6 prefixes for CLAT-side
addresses SHOULD use the same prefix." that is described on and PLAT-side IPv4 addresses and therefore does not comply
Section 3.3 in [RFC6052] due to using different IPv6 prefixes with the sentence "Both IPv4-translatable IPv6 addresses and
for CLAT-side and PLAT-side IPv4 addresses. IPv4-converted IPv6 addresses SHOULD use the same prefix." in
Section 3.3 of [RFC6052]. The CLAT does not facilitate
communications between a local IPv4-only node and an IPv6-
only node on the Internet.
5. Motivation and Uniqueness of 464XLAT 5. Motivation and Uniqueness of 464XLAT
1. Minimal IPv4 resource requirements, maximum IPv4 efficiency 1. Minimal IPv4 resource requirements, maximum IPv4 efficiency
through statistical multiplexing. through statistical multiplexing.
2. No new protocols required, quick deployment. 2. No new protocols required, quick deployment.
3. IPv6-only networks are simpler and therefore less expensive to 3. IPv6-only networks are simpler and therefore less expensive to
operate. operate than dual-stack networks.
4. Consistent native IP based monitoring, traffic engineering, and
capacity planning techniques can be applied without the
indirection or obfuscation of a tunnel.
6. Network Architecture 6. Network Architecture
Examples of 464XLAT architectures are shown in the figures in the Examples of 464XLAT architectures are shown in the figures in the
following sections. following sections.
Wireline Network Architecture can fit in the situations where there Wireline Network Architecture can fit in the situations where there
are clients behind the CLAT in the same way regardless of the type of are clients behind the CLAT in the same way regardless of the type of
access service, for example FTTH, DOCSIS, or WiFi. access service, for example FTTH, DOCSIS, or WiFi.
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| | | | \ GGSN / | | \ / | | | | \ GGSN / | | \ /
| | +------+ \ ' +------+ `----+---' | | +------+ \ ' +------+ `----+---'
| +-----+ | | `-------' | | +-----+ | | `-------' |
| | v4p +---+ | +--+---+ | | v4p +---+ | +--+---+
| +-----+ | | | v4g | | +-----+ | | | v4g |
+----------------------+ | host | +----------------------+ | host |
+------+ +------+
<- v4p -> XLAT <--------- v6 --------> XLAT <- v4g -> <- v4p -> XLAT <--------- v6 --------> XLAT <- v4g ->
v6 : Global IPv6 v6 : Global IPv6
v4p : Private IPv4 v4p : Private IPv4
v4g : Global IPv4 v4g : Global IPv4
PDP : Packet Data Protocol
GGSN : Gateway GPRS Support Node
Figure 2: Wireless 3GPP Network Topology Figure 2: Wireless 3GPP Network Topology
7. Applicability 7. Applicability
7.1. Wireline Network Applicability 7.1. Wireline Network Applicability
When an ISP has IPv6 access service and provides 464XLAT, the ISP can When an Internet Service Provider (ISP) has IPv6 access service and
provide outgoing IPv4 service to end users across an IPv6 access provides 464XLAT, the ISP can provide outgoing IPv4 service to end
network. The result is that edge network growth is no longer tightly users across an IPv6 access network. The result is that edge network
coupled to the availability of scarce IPv4 addresses. growth is no longer tightly coupled to the availability of scarce
IPv4 addresses.
If another ISP operates the PLAT, the edge ISP is only required to If another ISP operates the PLAT, the edge ISP is only required to
deploy an IPv6 access network. All ISPs do not need IPv4 access deploy an IPv6 access network. All ISPs do not need IPv4 access
networks. They can migrate their access network to a simple and networks. They can migrate their access network to a simple and
highly scalable IPv6-only environment. highly scalable IPv6-only environment.
7.2. Wireless 3GPP Network Applicability 7.2. Wireless 3GPP Network Applicability
At the time of writing, in September 2012, the vast majority of At the time of writing, in January 2013, the vast majority of mobile
mobile networks are compliant to Pre-Release 9 3GPP standards. In networks are compliant to Pre-Release 9 3GPP standards. In Pre-
Pre-Release 9 3GPP networks, GSM and UMTS networks must signal and Release 9 3GPP networks, Global System for Mobile Communications
support both IPv4 and IPv6 Packet Data Protocol (PDP) attachments to (GSM) and Universal Mobile Telecommunications System (UMTS) networks
access IPv4 and IPv6 network destinations [RFC6459]. Since there are must signal and support both IPv4 and IPv6 Packet Data Protocol (PDP)
two PDPs required to support two address families, this is double the attachments to access IPv4 and IPv6 network destinations [RFC6459].
number of PDPs required to support the status quo of one address Since there are two PDPs required to support two address families,
family, which is IPv4. this is double the number of PDPs required to support the status quo
of one address family, which is IPv4.
For the cases of connecting to an IPv4 literal or IPv4 socket that For the cases of connecting to an IPv4 literal or IPv4 socket that
require IPv4 connectivity, the CLAT function on the UE provides a require IPv4 connectivity, the CLAT function on the UE provides a
private IPv4 address and IPv4 default route on the host for the private IPv4 address and IPv4 default route on the host for the
applications to reference and bind to. Connections sourced from the applications to reference and bind to. Connections sourced from the
IPv4 interface are immediately routed to the CLAT function and passed IPv4 interface are immediately routed to the CLAT function and passed
to the IPv6-only mobile network, destined for the PLAT. In summary, to the IPv6-only mobile network, destined for the PLAT. In summary,
the UE has the CLAT function that does a stateless translation the UE has the CLAT function that does a stateless translation
[RFC6145], but only when required by an IPv4-only scenario such as [RFC6145], but only when required by an IPv4-only scenario such as
IPv4 literals or IPv4-only sockets. The mobile network has a PLAT IPv4 literals or IPv4-only sockets. The mobile network has a PLAT
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8. Implementation Considerations 8. Implementation Considerations
8.1. IPv6 Address Format 8.1. IPv6 Address Format
The IPv6 address format in 464XLAT is defined in Section 2.2 of The IPv6 address format in 464XLAT is defined in Section 2.2 of
[RFC6052]. [RFC6052].
8.2. IPv4/IPv6 Address Translation Chart 8.2. IPv4/IPv6 Address Translation Chart
This chart offers a explanation about address translation This chart offers an explanation about address translation
architecture using combination of stateful translation at the PLAT architecture using a combination of stateful translation at the PLAT
and stateless translation at the CLAT. The client on this chart is and stateless translation at the CLAT. The client on this chart is
delegated IPv6 prefix from a prefix delegation mechanism such as delegated an IPv6 prefix from a prefix delegation mechanism such as
DHCPv6-PD [RFC3633], therefore it has a dedicated IPv6 prefix for DHCPv6-PD [RFC3633], therefore it has a dedicated IPv6 prefix for
translation. translation.
Destination IPv4 address Destination IPv4 address
+----------------------------+ +----------------------------+
| Global IPv4 address | | Global IPv4 address |
| assigned to IPv4 server | | assigned to IPv4 server |
+--------+ +----------------------------+ +--------+ +----------------------------+
| IPv4 | Source IPv4 address | IPv4 | Source IPv4 address
| server | +----------------------------+ | server | +----------------------------+
skipping to change at page 9, line 7 skipping to change at page 10, line 7
+--------+ Source IPv4 address +--------+ Source IPv4 address
+----------------------------+ +----------------------------+
| Private IPv4 address | | Private IPv4 address |
| assigned to IPv4 client | | assigned to IPv4 client |
+----------------------------+ +----------------------------+
Case of enabling only stateless XLATE on CLAT Case of enabling only stateless XLATE on CLAT
8.3. IPv6 Prefix Handling 8.3. IPv6 Prefix Handling
The CLAT SHOULD acquire a dedicated /64 prefix for the purpose of There are two relevant IPv6 prefixes that the CLAT must be aware of.
sending and receiving statelessly translated packets.
The CLAT MAY discover the PLAT-side translation IPv6 prefix used as a First, CLAT must know its own IPv6 prefixes. The CLAT SHOULD acquire
destination of the PLAT via a /64 for the uplink interface, a /64 for all downlink interfaces,
[I-D.ietf-behave-nat64-discovery-heuristic]. In the future some and a dedicated /64 prefix for the purpose of sending and receiving
other mechanisms, such as a new DHCPv6 option, will possibly be statelessly translated packets. When a dedicated /64 prefix is not
defined. available for translation from DHCPv6-PD [RFC3633], the CLAT MAY
perform NAT44 for all IPv4 LAN packets so that all the LAN originated
IPv4 packets appear from a single IPv4 address and are then
statelessly translated to one interface IPv6 address that is claimed
by the CLAT via NDP and defended with DAD.
When a dedicated /64 prefix is not available from DHCPv6-PD Second, the CLAT MUST discover the PLAT-side translation IPv6 prefix
[RFC3633], the CLAT MAY perform NAT44 for all IPv4 LAN packets so used as a destination of the PLAT. The CLAT will use this prefix as
that all the LAN originated IPv4 packets appear from a single IPv4 the destination of all translation packets that require stateful
address and are then statelessly translated to one IPv6 address that translation to the IPv4 Internet. It MAY discover the PLAT-side
is claimed by the CLAT via NDP and defended with DAD. translation prefix using [I-D.ietf-behave-nat64-discovery-heuristic].
In the future some other mechanisms, such as a new DHCPv6 option,
will possibly be defined to communicate the PLAT-side translation
prefix.
8.4. DNS Proxy Implementation 8.4. DNS Proxy Implementation
The CLAT SHOULD implement a DNS proxy as defined in [RFC5625]. The The CLAT SHOULD implement a DNS proxy as defined in [RFC5625]. The
case of an IPv4-only node behind the CLAT querying an IPv4 DNS server case of an IPv4-only node behind the CLAT querying an IPv4 DNS server
is undesirable since it requires both stateful and stateless is undesirable since it requires both stateful and stateless
translation for each DNS lookup. The CLAT SHOULD set itself as the translation for each DNS lookup. The CLAT SHOULD set itself as the
DNS server via DHCP or other means and proxy DNS queries for IPv4 and DNS server via DHCP or other means and proxy DNS queries for IPv4 and
IPv6 LAN clients. Using the CLAT enabled home router or UE as a DNS IPv6 LAN clients. Using the CLAT enabled home router or UE as a DNS
proxy is a normal consumer gateway function and simplifies the proxy is a normal consumer gateway function and simplifies the
traffic flow so that only IPv6 native queries are made across the traffic flow so that only IPv6 native queries are made across the
access network. The CLAT SHOULD allow for a client to query any DNS access network. DNS queries from the client that are not sent to the
server of its choice and bypass the proxy. DNS proxy on the CLAT MUST be allowed and are translated and
forwarded just like any other IP traffic.
8.5. CLAT in a Gateway 8.5. CLAT in a Gateway
The CLAT is a stateless translation feature which can be implemented The CLAT feature can be implemented in a common home router or mobile
in a common home router or mobile phone that has a tethering feature. phone that has a tethering feature. Routers with a CLAT feature
The router with CLAT function SHOULD provide common router services SHOULD also provide common router services such as DHCP of [RFC1918]
such as DHCP of [RFC1918] addresses, DHCPv6, and DNS service. addresses, DHCPv6, NDP with RA, and DNS service.
8.6. CLAT to CLAT communications 8.6. CLAT to CLAT communications
While CLAT to CLAT IPv4 communication may work when the client IPv4 464XLAT is a hub and spoke architecture focused on enabling IPv4-only
subnets do not overlap, this traffic flow is out of scope. 464XLAT is services over IPv6-only networks. ICE [RFC5245] MAY be used to
a hub and spoke architecture focused on enabling IPv4-only services support peer-to-peer communication within a 464XLAT network.
over IPv6-only networks.
9. Deployment Considerations 9. Deployment Considerations
9.1. Traffic Engineering 9.1. Traffic Engineering
Even if the ISP for end users is different from the PLAT provider Even if the ISP for end users is different from the PLAT provider
(e.g. another ISP), it can implement traffic engineering (e.g. another ISP), it can implement traffic engineering
independently from the PLAT provider. Detailed reasons are below: independently from the PLAT provider. Detailed reasons are below:
1. The ISP for end users can figure out IPv4 destination address 1. The ISP for end users can figure out IPv4 destination address
from translated IPv6 packet header, so it can implement traffic from translated IPv6 packet header, so it can implement traffic
engineering based on IPv4 destination address (e.g. traffic engineering based on IPv4 destination address (e.g. traffic
monitoring for each IPv4 destination address, packet filtering monitoring for each IPv4 destination address, packet filtering
skipping to change at page 12, line 9 skipping to change at page 13, line 24
Algorithm", RFC 6145, April 2011. Algorithm", RFC 6145, April 2011.
[RFC6146] Bagnulo, M., Matthews, P., and I. van Beijnum, "Stateful [RFC6146] Bagnulo, M., Matthews, P., and I. van Beijnum, "Stateful
NAT64: Network Address and Protocol Translation from IPv6 NAT64: Network Address and Protocol Translation from IPv6
Clients to IPv4 Servers", RFC 6146, April 2011. Clients to IPv4 Servers", RFC 6146, April 2011.
13.2. Informative References 13.2. Informative References
[I-D.ietf-behave-nat64-discovery-heuristic] [I-D.ietf-behave-nat64-discovery-heuristic]
Savolainen, T., Korhonen, J., and D. Wing, "Discovery of Savolainen, T., Korhonen, J., and D. Wing, "Discovery of
IPv6 Prefix Used for IPv6 Address Synthesis", the IPv6 Prefix Used for IPv6 Address Synthesis",
draft-ietf-behave-nat64-discovery-heuristic-11 (work in draft-ietf-behave-nat64-discovery-heuristic-13 (work in
progress), July 2012. progress), November 2012.
[RFC1918] Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and [RFC1918] Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and
E. Lear, "Address Allocation for Private Internets", E. Lear, "Address Allocation for Private Internets",
BCP 5, RFC 1918, February 1996. BCP 5, RFC 1918, February 1996.
[RFC3633] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic [RFC3633] Troan, O. and R. Droms, "IPv6 Prefix Options for Dynamic
Host Configuration Protocol (DHCP) version 6", RFC 3633, Host Configuration Protocol (DHCP) version 6", RFC 3633,
December 2003. December 2003.
[RFC5245] Rosenberg, J., "Interactive Connectivity Establishment
(ICE): A Protocol for Network Address Translator (NAT)
Traversal for Offer/Answer Protocols", RFC 5245,
April 2010.
[RFC5625] Bellis, R., "DNS Proxy Implementation Guidelines", [RFC5625] Bellis, R., "DNS Proxy Implementation Guidelines",
BCP 152, RFC 5625, August 2009. BCP 152, RFC 5625, August 2009.
[RFC6092] Woodyatt, J., "Recommended Simple Security Capabilities in [RFC6092] Woodyatt, J., "Recommended Simple Security Capabilities in
Customer Premises Equipment (CPE) for Providing Customer Premises Equipment (CPE) for Providing
Residential IPv6 Internet Service", RFC 6092, Residential IPv6 Internet Service", RFC 6092,
January 2011. January 2011.
[RFC6147] Bagnulo, M., Sullivan, A., Matthews, P., and I. van [RFC6147] Bagnulo, M., Sullivan, A., Matthews, P., and I. van
Beijnum, "DNS64: DNS Extensions for Network Address Beijnum, "DNS64: DNS Extensions for Network Address
 End of changes. 27 change blocks. 
88 lines changed or deleted 125 lines changed or added

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