Internet DRAFT - draft-chen-sunset4-traffic-migration
draft-chen-sunset4-traffic-migration
Network Working Group G. Chen
Internet-Draft China Mobile
Intended status: Standards Track October 15, 2012
Expires: April 18, 2013
Graceful IPv4 Sunset with Traffic Migration
draft-chen-sunset4-traffic-migration-00
Abstract
In order to make a graceful IPv4 sunset, this memo described a method
helping traffic migration to IPv6. With the growth of IPv6 traffic,
operators could safely turn off IPv4 and evolve to IPv6-only network.
In order to achieve the goal, new traffic-migration options have been
proposed in DHCPv6 and PCP. IPv6 traffic steering could be performed
using those configurations.
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
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 April 18, 2013.
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
Chen Expires April 18, 2013 [Page 1]
Internet-Draft traffic-migration October 2012
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Requirements Language . . . . . . . . . . . . . . . . . . . . . 3
3. Traffic Migration Technologies . . . . . . . . . . . . . . . . 4
4. Configurations with DHCPv6 Options . . . . . . . . . . . . . . 5
5. Configurations with PCP Options . . . . . . . . . . . . . . . . 5
6. Security Considerations . . . . . . . . . . . . . . . . . . . . 6
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 6
8.1. Normative References . . . . . . . . . . . . . . . . . . . 6
8.2. Informative References . . . . . . . . . . . . . . . . . . 7
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 7
Chen Expires April 18, 2013 [Page 2]
Internet-Draft traffic-migration October 2012
1. Introduction
The working group of Sunset4 was targeted to standardize technologies
that facilitate the graceful sunsetting of the IPv4 Internet in the
context of the exhaustion of IPv4 address space while IPv6 is
deployed. This memo has described the way to incrementally turn off
the IPv4 by steering traffic to IPv6 networks.
As imminent demands to IP address, the community has to seek a way to
accelerate IPv6. However, the tremendous success of the Internet has
adhered to IPv4 technologies. ISPs don't want to significantly
changed its IPv4 network. Dual stack[RFC4213] was designed to
provide complete support for both Internet protocols. It's the
simplest deployment model to enable IPv4 hosts to access the IPv4
Internet and IPv6 hosts to access the IPv6 Internet. With the
thoughtful considerations, e.g. happy eyeballs[RFC6555], white-
listing[RFC6589], dual-stack approach could ensure user experiences
as original as possible.
[RFC6180]recommended the native dual-stack connectivity model. Some
ISPs have already successfully deployed dual-stack networks, in which
the dual-stack capable devices integrate both IPv6 and IPv4
forwarding. In those cases, IPv4 and IPv6 data flows are ships-in-
the-night. [RFC6264]commentated such transition mechanism may be
lack of drive to motive IPv6 growth, since most end users are not
sufficiently expert to configure or maintain host-based IPv6
transition. If there are no IPv4 sunset technologies, IPv4
connectivity and traffic would still continue to represent the
majority of traffic in most ISP networks.
The IPv4 sunset should be graceful. The arbitrary IPv4 turning off
may don't help the IPv6 acceleration, but exacerbate the situation of
instable IPv6 connections and IPv4 incompability. [RFC6586] has
stated the concerns in a IPv6-only environment. It should be avoided
during the period of IPv4 sunset, especially in a commercial network.
Under those considerations, traffic migration could achieve the
graceful process with no impacts to services. This memo enumerates
several migration technologies in Section 3. The corresponding
configurations have been described afterwards.
2. 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].
Chen Expires April 18, 2013 [Page 3]
Internet-Draft traffic-migration October 2012
3. Traffic Migration Technologies
With the stress of IP address shortage, switching the whole ISP
network into IPv6-only would be considered a ultimate strategy. A
number of IPv6 transition technologies were proposed. Some of them
may likely be less optimal than equivalent technologies for native IP
connections, i.e. IPv6-only and dual-stack networks. Whereas, it
could help migrate IPv4 traffic to IPv6 network that is transparent
to user's experiences. The Figure show the architecture those
technologies apply to .
+---+ IPv4 +-----+ IPv4 +-----+ IPv4 /----------\
| UE|--------|Dual |--------------| |--------/ \
+---+ |Stack| | GW | | Internet |
+---+ IPv6 | CPE | IPv6 | | IPv6 | |
|UE |------- | |-------+------| |--------\ /
+---+ +-----+ | +-----+ \----------/
+------+
|Server|
+------+
Figure 1: Traffic Migration architecture
Traffic migration technologies could shift IPv4 traffic to IPv6
links. Meanwhile, the issues of IPv4 compability have been
thoroughly considered and addressed in those technologies. The
migration enforcement could be located on a end-host or dual-stack
CPE. Translations or tunnel could be performed at an enforcement
point. Following enumerates relevant technologies.
o Dual-stack Lite: it employs IPv4 over IPv6 tunnel on CPE. The
packages would be encapsulated in IPv6 and transmitted. GW would
decapsulate the IPv6 packages and perform IPv4/IPv4 NAT[RFC6333].
It should be noted that several technologies have been discussed
in Softwires working group recently. Those technologies could
also successfully switch traffic to IPv6 network.
o 464xlat: it employs double translation
framework[I-D.ietf-v6ops-464xlat]. CPE could receive IPv4
packages and make stateless translation[RFC6145] to IPv6. GW
adopts stateful NAT64 [RFC6146]processing.
o BIH: It employs host based translation[RFC6535]. Embedded BIH
module could translate IPv4 packages into IPv6 on a host. Such
process is transparent to IPv4 applications.
At a sunset stage, a devices(e.g. a host or CPE) would observe the
appearance of enabling messages to discover the availability of
Chen Expires April 18, 2013 [Page 4]
Internet-Draft traffic-migration October 2012
migration technology. Thus, when an ISP decides to switch their
traffic to IPv6, the devices would detect and switch automatically to
traffic-migration mode.
4. Configurations with DHCPv6 Options
Enabling traffic migration could be achieved via DHCPv6. The
migration DHCPv6 option is proposed as below to inform the device
performing the traffic steering process. The format of the migration
option is shown in Figure 2.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OPTION_MIGRATION | option-len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mechanism |
+-+-+-+-+-+-+-+-+
option-code OPTION_MIGRATION(TBD)
option-len 1
mechanism This data is to indicate the particular
mechanism to be performed
Figure2: Migration Option for DHCPv6
The DHCPv6 client MUST include the OPTION_Migration option code in
the Option Request Option[RFC3315].
[Editor note: the mechanism filed informs the device that the
specific technology should be taken. This is very depending on the
ISP strategy and implementations. Weighting different options is
surely going beyond the scope of this document. Therefore, it should
be decided whether the particular semantics should be defined in the
draft.]
5. Configurations with PCP Options
It's also feasible to deliver such message in a NAT environment,
where there is coexistence of NAT44 and NAT64 on a network side. If
PCP clients are embedded in CPE or UE, new PCP options could help to
indicate migration preferring.
The format of migration PCP Option is depicted in Figure 3.
Chen Expires April 18, 2013 [Page 5]
Internet-Draft traffic-migration October 2012
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option Code | Reserved | Option Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mechanism |
+-+-+-+-+-+-+-+-+
option-code To be assigned by IANA
option-len 1
mechanism This data is to indicate the particular
mechanism to be performed
Figure3: Migration Option for PCP
A PCP Client MAY include a migration PCP Option in a MAP request to
learn network capability used by an upstream PCP-controlled device.
A PCP server controlling a NAT SHOULD be configured to return the
value to indicate if the migration technology should be enable. When
allowed, migration PCP Option conveys the value for the selection of
specific mechanism.
[Editor note: Same concern applies to the mechanism filed. it should
be decided whether the particular semantics should be defined in the
draft. ]
6. Security Considerations
TBD
7. IANA Considerations
This document makes no request of IANA.
8. References
8.1. Normative References
[I-D.ietf-v6ops-464xlat]
Mawatari, M., Kawashima, M., and C. Byrne, "464XLAT:
Combination of Stateful and Stateless Translation",
draft-ietf-v6ops-464xlat-08 (work in progress),
September 2012.
Chen Expires April 18, 2013 [Page 6]
Internet-Draft traffic-migration October 2012
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
and M. Carney, "Dynamic Host Configuration Protocol for
IPv6 (DHCPv6)", RFC 3315, July 2003.
[RFC4213] Nordmark, E. and R. Gilligan, "Basic Transition Mechanisms
for IPv6 Hosts and Routers", RFC 4213, October 2005.
[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.
[RFC6333] Durand, A., Droms, R., Woodyatt, J., and Y. Lee, "Dual-
Stack Lite Broadband Deployments Following IPv4
Exhaustion", RFC 6333, August 2011.
[RFC6535] Huang, B., Deng, H., and T. Savolainen, "Dual-Stack Hosts
Using "Bump-in-the-Host" (BIH)", RFC 6535, February 2012.
8.2. Informative References
[RFC6180] Arkko, J. and F. Baker, "Guidelines for Using IPv6
Transition Mechanisms during IPv6 Deployment", RFC 6180,
May 2011.
[RFC6264] Jiang, S., Guo, D., and B. Carpenter, "An Incremental
Carrier-Grade NAT (CGN) for IPv6 Transition", RFC 6264,
June 2011.
[RFC6555] Wing, D. and A. Yourtchenko, "Happy Eyeballs: Success with
Dual-Stack Hosts", RFC 6555, April 2012.
[RFC6586] Arkko, J. and A. Keranen, "Experiences from an IPv6-Only
Network", RFC 6586, April 2012.
[RFC6589] Livingood, J., "Considerations for Transitioning Content
to IPv6", RFC 6589, April 2012.
Chen Expires April 18, 2013 [Page 7]
Internet-Draft traffic-migration October 2012
Author's Address
Gang Chen
China Mobile
No.32 Xuanwumen West Street
Xicheng District
Beijing 100053
China
Email: phdgang@gmail.com
Chen Expires April 18, 2013 [Page 8]
