Network Working Group M. Boucadair
Internet-Draft France Telecom
Intended status: Standards Track E. Burgey
Expires: March 11, 2011 Orange Labs
September 7, 2010
A64: DNS Resource Record for IPv4-Embedded IPv6 Address
draft-boucadair-behave-dns-a64-02
Abstract
In the context of IPv4-IPv6 interconnection (or interworking),
several solutions have been proposed within IETF. Some of these
solutions require the definition of a new IPv4-Embedded IPv6 address
which is used to represent an IPv4-only host in an IPv6 realms and
the definition of a new mechanism called DNS64 for synthesizing a
AAAA record, representing an IPv4-Embedded IPv6 address in the DNS
system, from the A record representing the IPv4 address of the IPv4-
only host . This IPv4-Embedded IPv6 address, when managed by a
translator, is to be considered as "fake" address in a DNS system
since it is not necessarily assigned to any host's interface
qualified by the associated name.
This document defines a new DNS record type and query type to
identify IPv4-Embedded IPv6 address from native IPv6 ones. The new
record type and query type aim at helping the requesting party to
enforce its policies and avoid crossing NAT64 boxes when possible.
Native addresses are to be preferred.
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].
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
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time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on March 11, 2011.
Copyright Notice
Copyright (c) 2010 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Overall Context . . . . . . . . . . . . . . . . . . . . . 4
1.2. Contribution of this Draft . . . . . . . . . . . . . . . . 4
1.3. Backward Compatibility Issue . . . . . . . . . . . . . . . 5
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 6
3. Q/A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.1. Why a new RRType is Required? . . . . . . . . . . . . . . 7
3.2. Do We Need to Update all DNS Servers to Support this
New RRType? . . . . . . . . . . . . . . . . . . . . . . . 8
3.3. Does the Proposal Need Hosts to be Upgraded All? . . . . . 9
3.4. What is the Impact on the DNS Server Load? . . . . . . . . 10
3.5. Are legacy Hosts Impacted? . . . . . . . . . . . . . . . . 10
3.6. Location of Recursors . . . . . . . . . . . . . . . . . . 11
3.7. How an A64-compliant Host Can Discover an A64-DNS
Server? . . . . . . . . . . . . . . . . . . . . . . . . . 11
4. IPv4-Embedded IPv6 Record: A64 . . . . . . . . . . . . . . . . 12
4.1. A64 Record Type . . . . . . . . . . . . . . . . . . . . . 12
4.2. A64 Data Format . . . . . . . . . . . . . . . . . . . . . 12
4.3. A64 Query . . . . . . . . . . . . . . . . . . . . . . . . 12
4.4. Textual format of A64 records . . . . . . . . . . . . . . 12
4.5. IP64.INT Domain . . . . . . . . . . . . . . . . . . . . . 12
4.6. Modifications to Existing Query Types . . . . . . . . . . 12
4.7. On the Need of a New Query type . . . . . . . . . . . . . 13
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
6. Security Considerations . . . . . . . . . . . . . . . . . . . 13
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
8.1. Normative References . . . . . . . . . . . . . . . . . . . 14
8.2. Informative Reference . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
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1. Introduction
1.1. Overall Context
Due to IPv4 address depletion, several solutions have been proposed
within IETF. Among those solutions, IPv6 is the only perennial
solution that should be implemented by service providers.
Nevertheless, this implementation won't be in one shot and the co-
existence between IPv4 and IPv6 should be managed for a while. In
addition to the co-existence issue, interconnection means to enable
successful communications between IPv4 and IPv6 realms must be
enforced.
In this context, BEHAVE WG is currently specifying translator
mechanisms which cover both stateful
[I-D.ietf-behave-v6v4-xlate-stateful] and stateless
[I-D.ietf-behave-v6v4-xlate] modes. The proposed solutions require
the definition of a new IPv4-Embedded IPv6 address
[I-D.ietf-behave-address-format] which is used to represent an IPv4-
only host in an IPv6 realm. This type of addresses, when managed by
a translator, is to be considered as "fake" address since it is not
assigned to any host and can be confusing for the application. The
application querying for this address must be aware that the
application running on the host represented by the IPv4-Embedded IPv6
address is connected through an IPv4 interface and may be not able to
use a reference (e.g., [I-D.carpenter-behave-referral-object]) to an
IPv6 address in the packet payload.
When an IPv4-Embedded IPv6 address is used as destination address,
the traffic will be handled by a translator device and no direct
communication would be possible.
1.2. Contribution of this Draft
The aforementioned "fake" addresses should not be confused with
native IPv6 addresses in order to ease the enforcement of means to
avoid translators whenever possible. Notifying to the requesting
host that the resolved address is not a native address but an IPv4-
Embedded IPv6 address (which is behind a NAT) would ease the local
policies to prefer direct communications (i.e., avoid using IPv4-
mapped IPv6 addresses when a native IPv6 address or a native IPv4
address is available ).
For the sake of maintaining the reliability of the information
maintained and sent by DNS and helping a given host to enforce
policies to prefer native communications, a new record type is
proposed (A64). This record type stores only IPv4-Embedded IPv6
addresses. A new query type A64 is also defined to request A64
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records or synthesised A64 records.
This document does not make any assumption about the use of WKP or
LIR IPv6 prefix to build IPv4-Embedded IPv6 addresses. Both schemes
are supported.
1.3. Backward Compatibility Issue
The A64 record proposal suffers from DNS backward compatibility
issue. This issue is to be positioned in the following context:
o We are still in the early stages of IPv6 deployment and solutions
to help smooth migration and ease the transition to full IPv6
should be encouraged;
o IPv4-Embedded IPv6 addresses will be used in various architecture
configurations and guidelines for the use of these addresses to
populate DNS servers should be elaborated. This document is a
contribution to this effort;
o DNS64 proposal as defined in [I-D.ietf-behave-dns64] may be used
for serving dual-stack hosts (e.g., context of multi-homing. The
device may be attached to distinct domains managed by distinct
administrative entities. Means to ease the merging and the
consistency of the received information should be implemented, see
MIF WG problem statement). DNS servers do not have any means to
restrict the use of the service based on the requesting
connectivity capabilities. Appropriate solutions are to be put at
disposal of the client;
o [I-D.ietf-behave-dns64] does not define how to configure static
records using IPv4-Embedded IPv6 addresses;
o Not all DNS servers are to be upgraded. Only a subset of DNS
servers may be updated to support the A64 records.
o A procedure for the discovery of these A64-capable DNS servers is
described in [I-D.boucadair-behave-dns64-discovery]. When
supported, only the appropriate DNS servers will be invoked.
o In some contexts, referral procedure should be aware about the
type of the remote party (IPv4-only applications running on top of
an IPv6-only connected device). This may help avoiding "some"
ALGs in the path.
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2. Terminology
This document makes use of the following terms:
o Authoritative server: is a DNS server that answers authoritatively
for a given DNS query.
o Stub resolver: denotes a resolver with minimum functionality,
typically for use in end points that depend on a recursive
resolver.
o Recursive resolver: refers to a DNS server that accepts queries
from a resolver, and asks another resolver for the answer on
behalf of the first resolver.
o Synthetic resource record (RR): denotes a DNS resource record that
is not contained in any zone data file, but has been synthesized
from other RRs. An example of synthetic RR is a AAAA record
created from an A record.
o DNS64 function: refers to a function that is provisioned with one
or more IPv6 prefix(es) and is able to convert A64 records into
AAAA records if there is no AAAA native records and also able to
synthesize AAAA records from A records and the specific IPv6
prefix if there is no AAAA native records and no A64 records for
the requested QNAME. As explained in appendix B of
[I-D.ietf-behave-dns64] in some specific cases a DNS64 function
may generate a synthetic AAAA records even if a native AAAA
records still exists.
o DNS_A64 function: A logical function that is provisioned with one
or more IPv6 prefix(es) and is able to synthesize A64 records from
A records and the specific prefix if there is no A64 records for
the requested QNAME. As explained in appendix B of
[I-D.ietf-behave-dns64] in some specific case a DNS_A64 function
may generate a synthetic A64 records even if a native A64 records
(generated by an authoritative server) still exists.
o sDNS64 function : A simplified logical function that is able to
convert A64 records into AAAA records if there is no AAAA native
records. Such simplified function does not need to be provisioned
with a specific IPv6 prefix.
o Legacy DNS server : A DNS server that has not been updated to
manage A64 records and that does not include DNS64 function or
DNS_A64 function.
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o A64_DNS server : A DNS server that is able to store A64 records
and process A64 queries. An A64_DNS does not include any DNS_A64
function or any DNS64 function
o A64_DNS64 server: A server that provides all functionalities of a
standard DNS server and includes also a DNS_A64 function.
o DNS64 server: A server that provides all functionalities of a
standard DNS server and includes also a DNS64 function.
o A64_DNS64 recursor: A recursive resolver that provides all
functionalities of a standard DNS recursor and also provides the
DNS_A64 function as part of its operation.
o sDNS stub resolver : A stub resolver embedding a sDNS64 function
which is able to manage A64 records and to issue A64 queries.
3. Q/A
3.1. Why a new RRType is Required?
A new record type to enclose IPv4-Embedded IPv6 addresses is required
for the following reasons:
1. DNS64 proposal as defined in [I-D.ietf-behave-dns64] is tailored
for IPv6 only hosts. But it may be confusing for dual-stack
hosts receiving an A records and a AAAA records for the same
QNAME. If a native IPv6 address is enclosed in the DNS response,
IPv6 communication should be selected. If the AAAA record
contains an IPv4-Embedded IPv6 address, the dual-stack host
should prefer direct IPv4 communications to avoid problems that
could appear due to application layer gateway translation in the
NAT64. Without an additional mechanism providing information of
the nature of the address in the AAAA records or without a
mechanism to restrict the use of the DNS64 service based on the
requesting connectivity capabilities, dual-stack hosts won't be
able to take appropriate decisions. Using A64 records for IPv4-
Embedded IPv6 address is a way to distinguish them from native
IPv6 address using AAAA records;
2. [I-D.ietf-behave-dns64] points out in appendix A.4 the needs to
introduce IPv4-Embedded IPv6 address in DNS server that are
authoritative for a specific QNAME. The IPv6 prefix used to
build this IPv4-Embedded IPv6 address has been chosen by the
administrator of the requested QNAME and is not necessarily known
by the operator providing the Internet access service to the
requesting host. So to solve this problem, a mechanism is needed
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to exchange information between Internet access provider to
distinguish an IPv4-Embedded IPv6 address from a native IPv6
address. Exchanging A64 records for IPv4-Embedded IPv6 address
instead of AAAA records between DNS recursors and authoritative
server solves this issue;
3. [I-D.ietf-behave-dns64] describes in appendix B cases where both
IPv4-Embedded IPv6 address and native IPv6 can be returned in
AAAA records and points out that without a specific mechanism to
distinguish between them the standard process may choose the
IPv4-Embedded IPv6 address. Using A64 records for IPv4-Embedded
IPv6 address solves this issue;
4. A dual-stack application receiving an IPv4-Embedded IPv6 address
is not aware that the destination application entity is using an
IPv4 address. That application entity may not be able to
understand any reference in the packet payload to an IPv6
address. With the introduction of A64 records, it is possible to
develop a new API so that updated (i.e., A64-compliant) dual-
stack applications are able to learn that the IPv6 address comes
from an A64 records and is an IPv4-Embedded IPv6 address.
Operating systems with this new API may embed a sDN64 function to
deal with non updated IPv6 applications (i.e., non A64 compliant
applications).
It was tempting to define only a new query type to indicated whether
an enclosed AAAA record does not carry a native IPv6 address, but
this does not allow configuring static entries in the DNS pointing to
IPv4-Embedded IPv6 addresses.
3.2. Do We Need to Update all DNS Servers to Support this New RRType?
No.
A64_DNS servers or A64_DNS64 recursors are fully compatible with
legacy DNS servers, recursors or stub resolvers because the answer to
AAAA or to A queries and the recording or caching of AAAA records and
A records in not modified. So they can be introduced in the existing
DNS system without any trouble.
Owing to the DNS64 discovery mechanism described in
[I-D.boucadair-behave-dns64-discovery], DNS64 recursors or A64_DNS64
recursor are able to distinguish A64-capable DNS servers from legacy
DNS servers.
A64 resolvers, A64_DNS64 recursors or DNS64 recursors can issue non
recursive requests to other servers to retrieve the address of an
authoritative server for the QNAME and then use the A64 and DNS64
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discovery mechanism to check if this authoritative server is an
A64_DNS server. If the answer is that there is no A64_DNS server in
this domain, this means that there is no A64 records for this QNAME,
if the answer is the address of another A64_DNS server that is also
authoritative for that domain, the resolver will send this request to
this new server. With such a mechanism only one authoritative DNS
server for this domain including IPv4-Embedded IPv6 must be upgraded
toward to be A64-capable DNS. All intermediate DNS servers may be
legacy DNS servers.
Only authoritative DNS servers recording an IPv4-Embedded IPv6
address must be updated to be A64-capable DNS servers but they don't
need DNS64 or A64DN64 function. The IPv4-Embedded IPv6 address can
be provisioned by standard processing. A DNS_A64 function may just
be useful to simplify the provisioning process.
As in the [I-D.ietf-behave-dns64] proposal, only the DNS recursor
serving IPv6-only host using the NAT64 service needs to be upgraded
toward DNS64 recursor or A64_DNS64 recursor.
Other DNS recursor or DNS server can be legacy DNS server.
3.3. Does the Proposal Need Hosts to be Upgraded All?
No.
The DNS64 function is introduced to ensure compatibility with hosts
or CPEs that are not updated. In a first step, to use the NAT64
service, it is not necessary to upgrade existing hosts or existing
CPEs. It is sufficient to add a DNS64 recursor without modifying the
legacy DNS recursor. During the DNS address provisioning phase
(e.g., using DHCP or PPP), the Internet access service provider
provisions the (one or a list of) IP address of a DNS recursor
according to the connectivity option subscribed by the customer
(i.e., IPv4 only, dual-stack or IPv6 only). For IPv4 only or dual-
stack customers, the legacy DNS recursor or an A64_DNS64 recursor is
recommended. For IPv6 only customer a DNS64 recursor is recommended.
During this first step, dual-stack hosts will never received IPv4-
Embedded IPv6 address even if they are recorded in an authoritative
A64 DNS server. IPv6 only hosts will have access to all NAT64. Some
remaining issues of this first step are:
1. IPv6 applications running on IPv6 only host are not able to
recognize that the application running on the other host may be
IPv4 only and they may experience problem if they exchange
reference to an IPv6 address.
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2. IPv4 only applications running on dual-stack host are not able to
access to NAT64 service.
To solve the remaining issues, dual-stack hosts and CPEs must be
upgraded with sDNS stub resolver and the legacy DNS recursor provided
by the Internet access provider must be updated to an A64_DNS64
recursor. In the meantime, applications that want to distinguish
IPv4-Embedded IPv6 addresses from native IPv6 ones must be upgraded
to use a specific API to request A64 records.
The A64 and DNS64 discovery mechanism
[I-D.boucadair-behave-dns64-discovery] can be used by dual-stack
upgraded hosts to modify the pre-configured DNS recursor address with
a A64_DNS64 recursor address.
As a result, upgraded hosts will be able to use the A64 and DNS64
discovery mechanism to modify their configuration if the DNS recursor
address, provided by the Internet service access provider, is not the
most appropriate one.
3.4. What is the Impact on the DNS Server Load?
The impact on the DNS server load would be low.
There is no need to store, in DNS system, information about the
addressing capacity of hosts and the request/answer process remain
fully stateless.
The amount of data to be stored in A64_DNS server, A64_DNS64 recursor
or DNS64 recursor may increase if, for the same QNAME, both A64
records and AAAA records are present. But, this situation would be
scarce.
Compared to DNS64 proposal [I-D.ietf-behave-dns64], a DNS64 recursor
or an A64_DNS64 recursor can send three requests instead of two
generating therefore extra processing in the DNS server, in the DNS64
recursor and in the A64_DNS64 recursor. But this extra processing
can be avoided if a new request asking for AAAA, A64 and A records is
specified (see [I-D.li-dnsext-ipv4-ipv6]).
3.5. Are legacy Hosts Impacted?
No.
Legacy hosts are not impacted because the AAAA and the A records
processing is the same in A64_DNS64 recursors and/or in A64_DNS
servers as in legacy DNS servers.
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If dual-stack or IPv4 only legacy hosts are provisioned with the
address of a legacy DNS recursor or of an A64_DNS64 recursor, as
recommended in this document, they will not be impacted.
If IPv6 only legacy hosts are provisioned with the address of a
legacy DNS recursor or of an A64_DNS64 recursor, they will not be
impacted.
If IPv6 only legacy hosts are provisioned with the address of a DNS64
recursor they will benefits from the NAT64 service.
3.6. Location of Recursors
Specific DNS64 and A64_DNS64 recursors are introduced in this
document.
A DNS64 function must not be implemented in an authoritative server
(for QNAME this server is authoritative for).
A DNS_A64 function must not be implemented in an authoritative server
(for the QNAME this server is authoritative for) except for
provisioning new A64 records in the DNS server.
The DNS64 recursor and the A64_DNS64 recursor must be the first DNS
recursor managed by the operator providing the NAT64 service
requested by the customer. The request coming from the stub-resolver
of the host can pass only through recursors that are managed locally
like a DNS recursor in a CPE before being intercepted by a DNS64
recursor or the A64_DNS64 recursor.
The DNS64 recursor or the A64_DNS64 recursor should not accept
requests coming from other recursors managed by the operator or from
recursors managed by another Internet service provider. This is
generally achieved by providing the address of the DNS64 recursor or
A64_DNS64 recursor only to hosts or CPEs managed by customers of the
Internet service provider. The address of an A64 DNS server (it may
be an A64 DNS recursor) or a legacy DNS server may be provided to all
other DNS servers, recursors or resolvers.
3.7. How an A64-compliant Host Can Discover an A64-DNS Server?
By default an host is provisioned by the Internet service provider
with the address of a recursor. But an A64-compliant host can change
this allocation for a most appropriate one thanks to the mechanism
described in [I-D.boucadair-behave-dns64-discovery].
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4. IPv4-Embedded IPv6 Record: A64
[I-D.ietf-behave-address-format] discusses issues related to how an
IPv4 host can be represented in the IPv6 realm. A new address format
is proposed. To store an IPv4-Embedded IPv6 address
[I-D.ietf-behave-address-format], a new record type is defined.
4.1. A64 Record Type
The A64 resource record type is a record specific to the Internet
class that is destined to store a single IPv4-Embedded IPv6 address.
A type value is to be assigned by IANA.
4.2. A64 Data Format
Same data format for as AAAA records [RFC3596].
4.3. A64 Query
An A64 query for a specified domain name in the Internet class
returns all associated A64 resource records in the answer section of
a response. As AAAA query type, a type A64 query does not perform
additional section processing.
4.4. Textual format of A64 records
Same as for AAAA records [RFC3596].
4.5. IP64.INT Domain
In order to not pollute IP6.INT domain with IPv4-inferred records, a
new domain SHOULD be defined.
The same requirements as those of IP6.INT are to be taken into
account for IP64.INT.
[Editor note: input on the need of a dedicated domain or use IP6.INT
would be welcomed. Authors are in favour of separating both domains
in order to ease migration to IPv6-only Internet and avoid
interference which may be induced by transition mechanisms.]
4.6. Modifications to Existing Query Types
All existing query types that perform type A and AAAA processing
SHOULD be updated to perform type A, AAAA and A64 processing.
Only AAAA records SHOULD be returned when AAAA only type is specified
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in the query.
But during a transition phase, some hosts with IPv6-only connectivity
may not be updated to perform A64 queries. Specific IPv6 DNS
servers, called DNS64 recursors, may be used to serve those hosts. A
DNS64 recursor may return an A64 record as a response to AAAA query
if no AAAA record is available for the specified resource (A64
records are converted to AAAA records in the answer). This behaviour
advocates for enhancing the chance for a communication to be
established even through a translator). DNS64 recursors SHOULD not
be used by dual-stack hosts which do not support A64 query type.
When A64 query type is received, only A64 record type MUST be
returned.
4.7. On the Need of a New Query type
In the context of IPv4-IPv6 co-existence, new query type(s) would be
required to achieve the following goals:
o Retrieve both A64 and AAAA records by issuing one single query;
o Retrieve both IPv4 and IPv6 records (i.e., A, A64 and AAAA)
records by issuing one single query;
A candidate solution is described in [I-D.li-dnsext-ipv4-ipv6].
5. IANA Considerations
A record TYPE is to be assigned by IANA.
6. Security Considerations
This document does not introduce any security threat to the DNS
system.
7. Acknowledgements
Authors would like to thank Andrew Sullivan for his constructive
comments.
8. References
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8.1. Normative References
[RFC1034] Mockapetris, P., "Domain names - concepts and facilities",
STD 13, RFC 1034, November 1987.
[RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, November 1987.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3596] Thomson, S., Huitema, C., Ksinant, V., and M. Souissi,
"DNS Extensions to Support IP Version 6", RFC 3596,
October 2003.
8.2. Informative Reference
[I-D.boucadair-behave-dns64-discovery]
Boucadair, M. and E. Burgey, "DNS64 Service Location and
Discovery, draft-boucadair-behave-dns64-discovery-00",
October 2009.
[I-D.carpenter-behave-referral-object]
Carpenter, B., Boucadair, M., Halpern, J., Jiang, S., and
K. Moore, "A Generic Referral Object for Internet
Entities", draft-carpenter-behave-referral-object-01 (work
in progress), October 2009.
[I-D.ietf-behave-address-format]
Bao, C., Huitema, C., Bagnulo, M., Boucadair, M., and X.
Li, "IPv6 Addressing of IPv4/IPv6 Translators",
draft-ietf-behave-address-format-10 (work in progress),
August 2010.
[I-D.ietf-behave-dns64]
Bagnulo, M., Sullivan, A., Matthews, P., and I. Beijnum,
"DNS64: DNS extensions for Network Address Translation
from IPv6 Clients to IPv4 Servers",
draft-ietf-behave-dns64-10 (work in progress), July 2010.
[I-D.ietf-behave-v6v4-xlate]
Li, X., Bao, C., and F. Baker, "IP/ICMP Translation
Algorithm", draft-ietf-behave-v6v4-xlate-22 (work in
progress), August 2010.
[I-D.ietf-behave-v6v4-xlate-stateful]
Bagnulo, M., Matthews, P., and I. Beijnum, "Stateful
NAT64: Network Address and Protocol Translation from IPv6
Boucadair & Burgey Expires March 11, 2011 [Page 14]
Internet-Draft A64 DNS Record September 2010
Clients to IPv4 Servers",
draft-ietf-behave-v6v4-xlate-stateful-12 (work in
progress), July 2010.
[I-D.li-dnsext-ipv4-ipv6]
Li, L., Li, Z., and X. Duan, "DNS Extensions to Support
IPv4 and IPv6", draft-li-dnsext-ipv4-ipv6-02 (work in
progress), October 2009.
Authors' Addresses
Mohamed Boucadair
France Telecom
3, Av Francois Chateau
Rennes, 35000
France
Email: mohamed.boucadair@orange-ftgroup.com
Eric Burgey
Orange Labs
38-40, rue du general Leclerc
Issy-les-Moulineaux Cedex 9 92794
France
Email: eric.burgey@orange-ftgroup.com
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