< draft-mawatari-softwire-464xlat-01.txt   draft-mawatari-softwire-464xlat-02.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: Informational M. Kawashima Intended status: Informational M. Kawashima
Expires: April 26, 2012 NEC AccessTechnica, Ltd. Expires: May 3, 2012 NEC AccessTechnica, Ltd.
October 24, 2011 C. Byrne
T-Mobile USA
October 31, 2011
464XLAT: Combination of Stateful and Stateless Translation 464XLAT: Combination of Stateful and Stateless Translation
draft-mawatari-softwire-464xlat-01 draft-mawatari-softwire-464xlat-02
Abstract Abstract
This document describes a method (464XLAT) for IPv4 connectivity This document describes a method (464XLAT) for IPv4 connectivity
across IPv6 network by combination of stateful translation and across IPv6 network by combination of stateful translation and
stateless translation. 464XLAT is a simple technique to provide IPv4 stateless translation. 464XLAT is a simple technique to provide IPv4
access service while avoiding encapsulation just by using twice IPv4/ access service while avoiding encapsulation by using twice IPv4/IPv6
IPv6 translation standardized in [RFC6145] and [RFC6146]. translation standardized in [RFC6145] and [RFC6146].
Status of this Memo Status of this Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on April 26, 2012. This Internet-Draft will expire on May 3, 2012.
Copyright Notice Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Requirements Language . . . . . . . . . . . . . . . . . . . . . 3 2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3
3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Network Architecture . . . . . . . . . . . . . . . . . . . . . 4 4. Network Architecture . . . . . . . . . . . . . . . . . . . . . 4
5. Applicability . . . . . . . . . . . . . . . . . . . . . . . . . 4 4.1. Wireline Network Architecture . . . . . . . . . . . . . . 4
6. Implementation Considerations . . . . . . . . . . . . . . . . . 4 4.2. Wireless 3GPP Network Architecture . . . . . . . . . . . . 5
6.1. IPv6 Address Format . . . . . . . . . . . . . . . . . . . . 4 5. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 5
6.2. DNS Proxy Implementation . . . . . . . . . . . . . . . . . 5 5.1. Wireline Network Applicability . . . . . . . . . . . . . . 5
6.3. IPv6 Fragment Header Consideration . . . . . . . . . . . . 5 5.2. Wireless 3GPP Network Applicability . . . . . . . . . . . 6
6.4. Auto Prefix Assignment . . . . . . . . . . . . . . . . . . 5 6. Implementation Considerations . . . . . . . . . . . . . . . . 6
7. Deployment Considerations . . . . . . . . . . . . . . . . . . . 5 6.1. IPv6 Address Format . . . . . . . . . . . . . . . . . . . 6
8. Security Considerations . . . . . . . . . . . . . . . . . . . . 6 6.2. DNS Proxy Implementation . . . . . . . . . . . . . . . . . 7
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6 6.3. IPv6 Fragment Header Consideration . . . . . . . . . . . . 7
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 6 6.4. Auto Prefix Assignment . . . . . . . . . . . . . . . . . . 7
11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7. Deployment Considerations . . . . . . . . . . . . . . . . . . 7
11.1. Normative References . . . . . . . . . . . . . . . . . . . 7 8. Security Considerations . . . . . . . . . . . . . . . . . . . 8
11.2. Informative References . . . . . . . . . . . . . . . . . . 7 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 7 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 8
11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 9
11.1. Normative References . . . . . . . . . . . . . . . . . . . 9
11.2. Informative References . . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 10
1. Introduction 1. Introduction
The IANA unallocated IPv4 address pool was exhasuted on February 3, The IANA unallocated IPv4 address pool was exhasuted on February 3,
2011. It is likely that each RIR's unallocated IPv4 addres pool will 2011. It is likely that each RIR's unallocated IPv4 address pool
exhaust in the near future. In this situation, it will be difficult will exhaust in the near future. In this situation, it will be
for most ISPs to assign global IPv4 address to end users. difficult for many networks to assign IPv4 address to end users
despite substantial IPv4 connectivity required for mobile devices,
smart-grid, and cloud nodes.
This document describes an IPv4 over IPv6 solution as one of the This document describes an IPv4 over IPv6 solution as one of the
measures of IPv4 address exhaustion and encouragement of IPv6 measures of IPv4 address extension and encouragement of IPv6
deployment. deployment.
This method (464XLAT) in this document is using twice IPv4/IPv6 The 464XLAT method described in this document uses twice IPv4/IPv6
translation standardized in [RFC6145] and [RFC6146]. It does not translation standardized in [RFC6145] and [RFC6146]. It does not
need DNS64 [RFC6147] technology for the purpose of providing IPv4 require DNS64 [RFC6147], but it may use DNS64. It is also possible
over IPv6 service by this method. It is also possible to provide to provide single IPv4/IPv6 translation service, which will be needed
single IPv4/IPv6 translation service, which will be needed in the in the near future. This feature is one of the advantages, because
near future. This feature is one of the advantages, because it can it can be an encouragement to gradually transition to IPv6.
be an encouragement to gradually transition to IPv6.
This method is a combination of existing technologies and provides a
simple way of providing connectivity to the IPv4 Internet without the
use of a CGN nor a port mapping algorithm.
2. Requirements Language 2. 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].
3. Terminology 3. Terminology
PLAT: PLAT is Provider side translator(XLAT). A stateful PLAT: PLAT is Provider side translator(XLAT). A stateful
skipping to change at page 4, line 9 skipping to change at page 4, line 9
hosts in end-user network. Furthermore, it has DNS Proxy hosts in end-user network. Furthermore, it has DNS Proxy
function with IPv6 transport that provides name resolution function with IPv6 transport that provides name resolution
for IPv4 hosts and IPv6 hosts in end-user network. The for IPv4 hosts and IPv6 hosts in end-user network. The
presence of DNS64 [RFC6147] and any port mapping algorithm presence of DNS64 [RFC6147] and any port mapping algorithm
are not required. are not required.
4. Network Architecture 4. Network Architecture
464XLAT method is shown in the following figure. 464XLAT method is shown in the following figure.
4.1. Wireline Network Architecture
---- ----
| v6 | | v6 |
---- ----
| |
---- | .---+---. .------. ---- | .---+---. .------.
| v6 |-----+ / \ / \ | v6 |-----+ / \ / \
---- | ------ / IPv6 \ ------ / IPv4 \ ---- | ------ / IPv6 \ ------ / IPv4 \
+---| CLAT |---+ Internet +---| PLAT |---+ Internet | +---| CLAT |---+ Internet +---| PLAT |---+ Internet |
------- | ------ \ / ------ \ / ------- | ------ \ / ------ \ /
|v4p/v6 |--+ `---------' `----+----' |v4p/v6 |--+ `---------' `----+----'
------- | | ------- | |
----- | ----- ----- | -----
| v4p |----+ | v4g | | v4p |----+ | v4g |
----- | ----- ----- | -----
<- 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
Figure 1: Network Topology Figure 1: Wireline Network Topology
4.2. Wireless 3GPP Network Architecture
----
| v6 |
----
|
.---+---.
/ \
/ IPv6 \
| Internet |
\ /
UE / Mobile Phone `---------'
+----------------------+ |
| ---- | | .---+---. .------.
| | v6 |----+ | / \ / \
| ---- | ------| / IPv6 PDP \ ------ / IPv4 \
| +---| CLAT |---+ Mobile Core +---| PLAT |--+ Internet |
| | ------| \ GGSN / ------ \ /
| | | \ ' `----+---'
| ------ | | `-------' |
| | v4p |---+ | -----
| ------ | | | v4g |
+----------------------+ -----
<- v4p -> XLAT <--------- v6 --------> XLAT <- v4g ->
v6 : Global IPv6
v4p : Private IPv4
v4g : Global IPv4
Figure 2: Wireless 3GPP Network Topology
5. Applicability 5. Applicability
5.1. Wireline Network Applicability
When ISP has IPv6 access network infrastructure and 464XLAT, ISP can When ISP has IPv6 access network infrastructure and 464XLAT, ISP can
provide IPv4 service to end users. provide IPv4 service to end users.
If the IXP or another provider operates the PLAT, all ISPs have to do If the IXP or another provider operates the PLAT, all ISPs have to do
is to deploy IPv6 access network. All ISPs do not need IPv4 is to deploy IPv6 access network. All ISPs do not need IPv4
facilities. They can migrate quickly their operation to an IPv6-only facilities. They can migrate quickly their operation to an IPv6-only
environment. Incidentally, Japan Internet Exchange(JPIX) is environment. Incidentally, Japan Internet Exchange(JPIX) is
providing 464XLAT trial service since July 2010. providing 464XLAT trial service since July 2010.
5.2. Wireless 3GPP Network Applicability
In pre-release 9 3GPP networks, GSM and UMTS networks must signal and
support both IPv4 and IPv6 PDP attachments to access IPv4 and IPv6
network destinations. This is generally not operationally viable
since much of the network cost is derived from the number of PDP
attachments, both in terms of licenses from the network hardware
vendors and in terms of actual hardware resources required to support
and maintain the PDP signaling and mobility events. This has been
one of the operational challenges of bringing IPv6 to mobile
networks, it simply costs more from the network provider perspective
and does not result in any new revenues, since customers are not
willing to pay for IPv6 access.
Now that both global and private IPv4 addresses are scarce to the
extent that it is a substantial business risk and limiting growth in
many areas, the mobile network providers must support IPv6 address
which solve the IP address scarcity issue, but it is not feasible to
simply turn on additional IPv6 PDP network attachments since that
does not solve the near-term IPv4 scarcity issues and at it also
increases cost. The most logical path forward is to replace IPv6
with IPv4 and replace the common NAT44 with NAT64 and DNS64.
Extensive live network testing with hundreds of friendly-users has
shown that IPv6-only network attachments for mobile devices covers
over 90% of the common use-cases in Symbian and Android mobile
operating systems. The remaining 10% of use-cases do not work
because the application requires an IPv4 socket or the application
references an IPv4-literal.
464XLAT in combination with NAT64 and DNS64 allows 90% of the
applications to continue to work with single translation while at the
sametime facilitating legacy IPv4-only applications by providing a
private IPv4 address and IPv4 route on the host for the applications
to reference and bind to. Traffic sourced from the IPv4 interface is
immediately routed the NAT46 CLAT function and passed to the IPv6-
only mobile network and destine to the PLAT NAT64.
6. Implementation Considerations 6. Implementation Considerations
6.1. IPv6 Address Format 6.1. IPv6 Address Format
IPv6 address format in 464XLAT is presented in the following format. IPv6 address format in 464XLAT is presented in the following format.
+-----------------------------------------------+---------------+ +-----------------------------------------------+---------------+
| XLAT prefix(96) | IPv4(32) | | XLAT prefix(96) | IPv4(32) |
+-----------------------------------------------+---------------+ +-----------------------------------------------+---------------+
skipping to change at page 5, line 37 skipping to change at page 7, line 37
difficulties in practice due to limited firewall fragmentation difficulties in practice due to limited firewall fragmentation
support, etc. Therefore, the PLAT and CLAT may provide a support, etc. Therefore, the PLAT and CLAT may provide a
configuration function that allows the PLAT and CLAT not to include configuration function that allows the PLAT and CLAT not to include
the Fragment Header for the non-fragmented IPv6 packets. At any the Fragment Header for the non-fragmented IPv6 packets. At any
rate, both behaviors SHOULD match. rate, both behaviors SHOULD match.
6.4. Auto Prefix Assignment 6.4. Auto Prefix Assignment
Source IPv6 prefix assignment in CLAT is via DHCPv6 prefix delegation Source IPv6 prefix assignment in CLAT is via DHCPv6 prefix delegation
or another method. Destination IPv6 prefix assignment in CLAT is via or another method. Destination IPv6 prefix assignment in CLAT is via
some method. (e.g., DHCPv6 option, TR-069, DNS, HTTP, etc.) some method. (e.g., DHCPv6 option, TR-069, DNS, HTTP,
[I-D.ietf-behave-nat64-discovery-heuristic], etc.)
7. Deployment Considerations 7. Deployment Considerations
Even if the Internet access provider for consumers is different from Even if the Internet access provider for consumers is different from
the PLAT provider (another Internet access provider or Internet the PLAT provider (another Internet access provider or Internet
exchange provider, etc.), it can implement traffic engineering exchange provider, etc.), 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 Internet access provider for consumers can figure out IPv4 1. The Internet access provider for consumers can figure out IPv4
source address and IPv4 destination address from translated IPv6 source address and IPv4 destination address from translated IPv6
skipping to change at page 6, line 15 skipping to change at page 8, line 16
for visualizing the inner IPv4 packet of the tunnel packet. for visualizing the inner IPv4 packet of the tunnel packet.
2. If the Internet access provider for consumers can assign IPv6 2. If the Internet access provider for consumers can assign IPv6
prefix greater than /64 for each subscriber, this 464XLAT method prefix greater than /64 for each subscriber, this 464XLAT method
can separate IPv6 prefix for native IPv6 packets and XLAT prefix can separate IPv6 prefix for native IPv6 packets and XLAT prefix
for IPv4/IPv6 translation packets. Accordingly, it can identify for IPv4/IPv6 translation packets. Accordingly, it can identify
the type of packets ("native IPv6 packets" and "IPv4/IPv6 the type of packets ("native IPv6 packets" and "IPv4/IPv6
translation packets"), and implement traffic engineering based on translation packets"), and implement traffic engineering based on
IPv6 prefix. IPv6 prefix.
And this 464XLAT method have two capabilities. One is a IPv6 -> IPv4 This 464XLAT method have two capabilities. One is a IPv6 -> IPv4 ->
-> IPv6 translation for sharing global IPv4 addresses, another is a IPv6 translation for sharing global IPv4 addresses, another is a IPv4
IPv4 -> IPv6 translation for reaching IPv6 only servers from IPv4 -> IPv6 translation for reaching IPv6 only servers from IPv4 only
only clients that can not support IPv6. IPv4 only clients will clients that can not support IPv6. IPv4 only clients will remain for
remain for a while. a while.
8. Security Considerations 8. Security Considerations
To implement a PLAT, see security considerations presented in Section To implement a PLAT, see security considerations presented in Section
5 of [RFC6146]. 5 of [RFC6146].
To implement a CLAT, see security considerations presented in Section To implement a CLAT, see security considerations presented in Section
7 of [RFC6145]. And furthermore, the CLAT SHOULD perform Bogon 7 of [RFC6145]. And furthermore, the CLAT SHOULD perform Bogon
filter, and SHOULD have IPv6 firewall function as a IPv6 router. It filter, and SHOULD have IPv6 firewall function as a IPv6 router. It
is useful function for native IPv6 packet and translated IPv6 packet. is useful function for native IPv6 packet and translated IPv6 packet.
skipping to change at page 7, line 25 skipping to change at page 9, line 25
[RFC6145] Li, X., Bao, C., and F. Baker, "IP/ICMP Translation [RFC6145] Li, X., Bao, C., and F. Baker, "IP/ICMP Translation
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.
11.2. Informative References 11.2. Informative References
[I-D.ietf-behave-nat64-discovery-heuristic]
Savolainen, T. and J. Korhonen, "Discovery of a Network-
Specific NAT64 Prefix using a Well-Known Name",
draft-ietf-behave-nat64-discovery-heuristic-03 (work in
progress), October 2011.
[I-D.ietf-v6ops-3gpp-eps]
Korhonen, J., Soininen, J., Patil, B., Savolainen, T.,
Bajko, G., and K. Iisakkila, "IPv6 in 3GPP Evolved Packet
System", draft-ietf-v6ops-3gpp-eps-08 (work in progress),
September 2011.
[I-D.murakami-softwire-4v6-translation] [I-D.murakami-softwire-4v6-translation]
Murakami, T., Chen, G., Deng, H., Dec, W., and S. Murakami, T., Chen, G., Deng, H., Dec, W., and S.
Matsushima, "4via6 Stateless Translation", Matsushima, "4via6 Stateless Translation",
draft-murakami-softwire-4v6-translation-00 (work in draft-murakami-softwire-4v6-translation-00 (work in
progress), July 2011. progress), July 2011.
[I-D.xli-behave-divi] [I-D.xli-behave-divi]
Bao, C., Li, X., Zhai, Y., and W. Shang, "dIVI: Dual- Bao, C., Li, X., Zhai, Y., and W. Shang, "dIVI: Dual-
Stateless IPv4/IPv6 Translation", draft-xli-behave-divi-03 Stateless IPv4/IPv6 Translation", draft-xli-behave-divi-04
(work in progress), July 2011. (work in progress), October 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
Translation from IPv6 Clients to IPv4 Servers", RFC 6147, Translation from IPv6 Clients to IPv4 Servers", RFC 6147,
April 2011. April 2011.
Authors' Addresses Authors' Addresses
Masataka Mawatari Masataka Mawatari
Japan Internet Exchange Co.,Ltd. Japan Internet Exchange Co.,Ltd.
skipping to change at line 308 skipping to change at page 10, line 24
Email: mawatari@jpix.ad.jp Email: mawatari@jpix.ad.jp
Masanobu Kawashima Masanobu Kawashima
NEC AccessTechnica, Ltd. NEC AccessTechnica, Ltd.
800, Shimomata 800, Shimomata
Kakegawa-shi, Shizuoka 436-8501 Kakegawa-shi, Shizuoka 436-8501
JAPAN JAPAN
Phone: +81 537 23 9655 Phone: +81 537 23 9655
Email: kawashimam@vx.jp.nec.com Email: kawashimam@vx.jp.nec.com
Cameron Byrne
T-Mobile USA
Bellevue, Washington 98105
USA
Email: cameron.byrne@t-mobile.com
 End of changes. 19 change blocks. 
48 lines changed or deleted 137 lines changed or added

This html diff was produced by rfcdiff 1.48. The latest version is available from http://tools.ietf.org/tools/rfcdiff/