V6OPS B. Carpenter
Internet-Draft Univ. of Auckland
Intended status: Informational S. Jiang
Expires: August 27, 2010 Huawei Technologies Co., Ltd
February 23, 2010
Emerging Service Provider Scenarios for IPv6 Deployment
draft-carpenter-v6ops-isp-scenarios-01
Abstract
This document describes scenarios that are emerging among Internet
Service Providers for the deployment of IPv6. They are based on
practical experience so far, as well as current plans and
requirements, but they are not intended as binding recommendations.
Status of this Memo
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Review of existing documents . . . . . . . . . . . . . . . . . 3
3. Review of ISP experience, plans and requirements . . . . . . . 6
4. Lessons from experience and planning . . . . . . . . . . . . . 8
5. Suggested scenarios . . . . . . . . . . . . . . . . . . . . . 9
6. Gap analysis . . . . . . . . . . . . . . . . . . . . . . . . . 9
7. Security Considerations . . . . . . . . . . . . . . . . . . . 11
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 11
10. Change log . . . . . . . . . . . . . . . . . . . . . . . . . . 11
11. Informative References . . . . . . . . . . . . . . . . . . . . 12
Appendix A. Summary of replies . . . . . . . . . . . . . . . . . 13
Appendix B. Questionnaire . . . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 19
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1. Introduction
As is well known, the approaching exhaustion of IPv4 address space
will bring about a situation in which Internet Service Providers
(ISPs) are faced with a choice between one or more of three major
alternatives:
1. Squeeze the use of IPv4 addresses even harder than today, using
smaller and smaller address blocks per customer, and possibly
trading address blocks with other ISPs.
2. Install multiple layers of network address translation, or share
IPv4 addresses by other methods such as address-plus-port mapping
[I-D.ymbk-aplusp], [I-D.boucadair-port-range].
3. Deploy IPv6, and operate IPv4-IPv6 coexistence and interworking
mechanisms.
This document focuses on alternative (3), while recognizing that many
ISPs may be obliged by circumstances to prolong the life of IPv4 by
using (1) or (2) while preparing for (3).
The document is intended as a guide to useful IPv6 deployment
scenarios. However, it is not a "cookbook" of operational recipes,
and the best choice of scenarios will depend on the circumstances of
individual ISPs.
We consider various aspects of IPv6 deployment: addressing, routing,
DNS, management and of course IPv4-IPv6 coexistence and interworking.
We do not consider application services in detail, but we do discuss
general aspects.
We first review several documents produced in the past by the IETF,
and mention relevant work in progress in the IETF. We then survey
requirements, plans, and practical experience from various ISPs.
Several deployment scenarios that result from that input are then
described; these are not formal recommendations, but are intended as
example scenarios which ISPs may choose to copy or modify to suit
their own technical, economic and regulatory situation. We conclude
with a gap analysis and security considerations.
2. Review of existing documents
The IETF's view of core IPv6 requirements is to be found in [RFC4294]
(currently being updated as [I-D.ietf-6man-node-req-bis]). However,
this does not give a complete view of mechanisms an ISP may need to
deploy, since it considers the requirements for an individual node,
not for a network as a whole.
[RFC4029] discusses scenarios for introducing IPv6 into ISP networks,
as the problem was viewed some years ago. The document is still
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valuable as a general introduction to the process that an ISP must
design, but it does not consider today's situation where IPv4
addresses have in practical terms run out, and interworking between
IPv6-only and IPv4-only clients and servers must be supported in
addition to basic dual-stack and tunneling scenarios. We can extract
a list of basic issues and needs from RFC 4029, using the RFC's own
terminology:
o Customer Premises Equipment (CPE) - must support IPv6, or allow
IPv6-in-IPv4 tunnels. CPE requirements and security are currently
being specified in [I-D.ietf-v6ops-ipv6-cpe-router] and
[I-D.ietf-v6ops-cpe-simple-security].
o Provider Edge Equipment (PE) - ditto.
o ISP backbone (core and border routers, switches if used) - support
dual stack, or allow IPv6-in-IPv4 tunnels. An alternative is a
newly built IPv6 backbone that allows IPv4-in-IPv6 tunnels.
o Network management and monitoring applications must take IPv6 into
account.
o Customer management (e.g., RADIUS) mechanisms must be able to
supply IPv6 prefixes and other information to customers.
o Accounting and billing mechanisms must support both versions.
o Security mechanisms must support both versions.
The end goal described in RFC 4029 is simply a dual-stack ISP
backbone. Today's view is that this is insufficient, as it does not
allow for interworking between IPv6-only and legacy (IPv4-only)
hosts. Indeed, the end goal today might be an IPv6-only ISP
backbone, with some form of legacy IPv4 support.
[RFC4779] discusses deployment in broadband access networks such as
CATV, ADSL and wireless. [RFC5181] deals specifically with IEEE
802.16 access networks. In some access scenarios, the access
protocol allows separately for IPv4 and IPv6, as for DOCSIS-based
CATV and for one variant of IEEE 802.16 [RFC5121]. In other
scenarios, the broadband service is essentially an emulation of raw
Ethernet, as for Wi-Fi, or for another variant of IEEE 802.16
[I-D.ietf-16ng-ip-over-ethernet-over-802-dot-16]. Another issue is
whether the ISP uses MPLS for back-haul from the access network, in
which case the 6PE [RFC4798] mechanism may be appropriate to carry
IPv6, with no need to change the IGP in any way.
[RFC4942] covers IPv6 security issues, especially those that are
specific to transition and coexistence scenarios. The main message
for ISPs is that the switch to IPv6 does not mean that IP layer
security issues will go away, and of course security issues that are
not specific to the IP layer will hardly change.
Also related to security, [RFC4864] discusses what is referred to as
"Local Network Protection", i.e., how the internal structure of a
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site network that is not hidden behind a network address translator
can be protected. Although not directly relevant to ISP operations,
this topic does affect the issue of how well an ISP's customers are
protected after they deploy IPv6.
[RFC5211] describes an independent view of a possible sequence of
events for IPv6 adoption in the Internet as a whole, with direct
implications for ISPs. Its main point, perhaps, is that by 2012 it
will be necessary to regard IPv4 networks as the legacy solution.
Although the basic IPv6 standards have long been stable, it should be
noted that considerable work continues in the IETF, particularly to
resolve the issue of highly scalable multihoming support for IPv6
sites, and to resolve the problem of IP layer interworking between
IPv6-only and IPv4-only hosts. Progress continues in various IETF
working groups that may affect ISP scenarios in due course.
o The 6MAN WG maintains the basic IPv6 standards. This work should
have little direct effect on ISPs.
o The V6OPS WG produces documents of direct interest for operational
practice as well as security practice. Current work includes CPE
requirements, CPE security, and Internet Exchange Point practice.
The present document will be discussed in V6OPS.
o The SOFTWIRE WG is working on additional protocols for IP-in-IP
tunnels in an ISP context.
o The BEHAVE WG is working on specifications for NAT64 and DNS64,
methods of supporting access from IPv6-only initiators to reach
IPv4-only services.
o The DHC WG maintains and extends DHCPv6.
o The SHIM6 WG is finalising work on a host-based protocol for IPv6
multihoming, based on the usage of multiple IPv6 prefixes for a
customer connected to multiple ISPs.
o The LISP WG is developing experimental standards for a scalable
tunnel-based routing mechanism which would, if successful, support
an alternative multihoming model.
Readers may find the current documents of these WGs via
<http://www.ietf.org/dyn/wg/charter.html>.
The IETF is not currently discussing IPv6/IPv4 interworking at the
transport or application layers. The former is not generally
considered to be a valuable approach. The latter is considered to be
handled within the original dual-stack model of IPv6 deployment:
either one end of an application session will have dual-stack
connectivity, or a dual-stack intermediary such as an HTTP proxy or
SMTP server will interface to both IPv4-only and IPv6-only hosts.
While valid and useful for many common applications, this approach
does not solve all possible interworking issues. In any case it does
not require further standards work at the network layer.
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3. Review of ISP experience, plans and requirements
To obtain a view of the IPv6 experience, plans and requirements of
ISPs, a questionnaire was issued in December 2009 and announced
widely to the operational community. We promised to keep the replies
strictly confidential and to publish only combined results, without
identifying information about individual ISPs in any published
results. The raw technical questions are shown in Appendix B, and a
detailed summary of the replies is in Appendix A. Note that although
the questionnaire was widely announced, those who chose to reply were
self-selected and we can make no claim of statistical significance or
freedom from bias in the results. In particular, we assume that ISPs
with a pre-existing interest in IPv6 are more likely to have replied
than others.
Thirty ISPs replied before the cutoff date for this analysis.
(Additional replies, if received by the end of April 2010, will be
included in a later version.) 66% of responses were from European
ISPs but large operators in North America and Asia/Pacific regions
are included. Commercial ISPs operating nationally predominate, with
a vast range of size (from 30 customers up to 40 million). Note that
some very large providers chose not to answer about the number of
customers.
80% of the respondents offer both transit and origin-only service;
27% offer IP multicast service; 80% have multihomed customers. A
very wide variety of access technologies is used: xDSL, DOCSIS,
leased line (X.25, TDM/PDH, SDH), frame relay, dialup, microwave,
FTTP, CDMA, UMTS, LTE, WiMAX, BWA, WiFi, Ethernet (100M-10G),
MetroEthernet/MPLS. Most ISPs provide CPE to some or all of their
customers, but these CPE are often unable to support IPv6.
Estimates of when ISPs will run out of public IPv4 address space for
internal use vary widely, between "now" and "never". Public IPv4
address space for customers is mainly expected to run out between
2010 and 2015, but three or four ISPs suggested it will never happen.
About 20% of ISPs offer RFC 1918 space to customers, and about 40%
use such addresses internally.
60% of ISPs report that some big customers are requesting IPv6.
Predictions for when 10% of customers will require IPv6 range from
2010 to 2017, and for 50% from 2011 to 2020. These ISPs require IPv6
to be a standard service by 2010 to 2015; the most common target date
is 2011. 40% already offer IPv6 as a regular service, although in
general it is used by fewer than 1% of customers. Another 47% of
ISPs have IPv6 deployment in progress or planned. These all plan at
least beta-test service in 2010. Planned dates for regular service
are between 2010 and 2013 (except for one ISP who replied that it
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depends on the marketing department). When asked when IPv6 will
reach 50% of total traffic, the most common answer is 2015.
Turning to technology choices, the overwhelming choice of approach
(93%) is a dual stack routing backbone, and the reason given is
simplicity and cost. 40% run, or plan to run, a 6to4 relay as well,
and 17% run or plan a Teredo server. However, 77% of ISPs don't have
or plan any devices dedicated to IPv6. A different 77% don't see
IPv6 as an opportunity to restructure their network topology.
When asked which types of equipment are unable to support IPv6, the
most common answer was CPE (9 mentions). Also mentioned: handsets;
DSLAMs; routers (including several specific models); traffic
management boxes; load balancers; VPN boxes; management interfaces &
systems; firewalls; billing systems. When asked if such devices can
be field-upgraded, the answers were gloomy: 5 yes, 4 partially, 10
no, and numerous "don't know" or "hopefully".
83% support or plan DNS AAAA queries over IPv6, and all but one of
these include reverse DNS lookup for IPv6.
The ISPs have prefixes ranging from /19 to /48, and have a variety of
policies for customer prefixes. Fifteen ISPs offer more than one of
/48, /52, /56, /60 or /64. Two offer /56 only, seven offer /48 only.
Two wired operators offer /64 only. Mobile operators offer /64 in
accordance with 3GPP, but at least one would like to be allowed to
offer /128 or /126. Also, as many as 30% of the operators already
have IPv6 customers preferring a PI prefix. The methods chosen for
prefix delegation to CPEs are manual, DHCPv6[-PD], SLAAC, RADIUS, and
PPoE.
About 50% of ISPs already operate or plan dual-stack SMTP, POP3, IMAP
and HTTP services. In terms of internal services, it seems that
firewalls, intrusion detection, address management, monitoring, and
network management tools are also around the 50% mark. However,
accounting and billing software is only ready at 23% of ISPs.
Considering IPv4-IPv6 interworking, 57% of ISPs don't expect to have
IPv6-only customers (but mobile operators are certain they will have
millions). Five ISPs report customers who explicitly refused to
consider IPv6. When asked how long customers will run IPv4-only
applications, the most frequent answer is "more than ten years".
Only three ISPs state that IPv6-IPv4 interworking at the the IP layer
is not needed. On the other hand, only three (a different three!)
run or plan to run NAT-PT. At least 30% plan to run some kind of
translator (presumably NAT64/DNS64), but only one felt that a
multicast translator was essential. Among those who do not plan a
translator, when asked how they plan to connect IPv6-only customers
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to IPv4-only services, seven rely on dual stack and three have no
plan (one said, paraphrasing, "it's their problem").
Asked about plans for Mobile IPv6 (or Nemo mobile networks), 20% said
yes, and 70% said no, with the others uncertain.
4. Lessons from experience and planning
This section is assembled and paraphrased from general comments made
in the various questionnaire responses. Any inconsistencies or
contradictions are present in the original data. Comments related to
missing features and products have been included in Section 6.
As noted in the summary above, the ISPs that responded largely prefer
a native dual stack deployment. Numerous comments mentioned the
simplicity of this model and the complexity and sub-optimal routing
of tunnel-based solutions. Topology redesign is not considered,
because congruent IPv4 and IPv6 topology simplifies maintenance and
engineering. Nevertheless, 6to4 is considered convenient for DOCSIS
users and 6RD is considered an attractive model by some. Various
operators, but by no means all, see a need for 6to4 and Teredo. One
MPLS-based operator prefers 6PE because it avoids an IPv6 IGP and
reduces operational costs. Another operator sees IPv4 scarcity
addressed by a DS-lite CGN, also acting as a catalyst for IPv6. One
operator with a very large NAT44 infrastructure believes that NAT64
will be similar to support.
Several ISPs observe that IPv6 deployment is technically not hard.
The most eloquent statement: "Just do it, bit by bit. It is very
much an 'eating the elephant' problem, but at one mouthful at a time,
it appears to be surprisingly easy." Despite the known gaps, the
tools and toolkits are fairly mature at this point. Managerial
commitment and a systematic approach to analysing requirements and
readiness are of course essential. Evangelization remains a must, as
it seems that many ISP and IT managers are still unaware of the need
for an IPv6 plan, and are inclined to dismiss IPv4 depletion as a
false alarm, and also seem unaware that NATs create expensive support
requirements. Without customers wanting IPv6, getting business
backing is very hard, and IPv6 security and scale was not a focus for
vendors until very recently. Also, operators lack real experience
with customer usage of IPv6, and the resulting lack of confidence
causes delay.
Three further quotations are of interest:
"We are planning to move all our management addressing from IPv4 to
IPv6 to free up IPv4 addresses."
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"I am actively pushing our larger customers to start testing IPv6 as
our development has pretty much stopped as we need some real world
testing to be done."
"Customer support needs to be aware that IPv6 is being started in
your network, or servers. We experienced many IPv6 blocking
applications, applications that do not fall back to IPv4, etc. The
most difficult part may be to get engineers, sales, customer support
personnel to like IPv6."
5. Suggested scenarios
This document does not make firm recommendations; the circumstances
of each ISP may be different. Rather, it describes several suggested
deployment scenarios that appear, from the analysis above, to have
the best operational characteristics. Each ISP should make its own
choices, according to its own technical, economic and regulatory
environment.
[[ NOTE: this section will be filled out after further discussions.
It will also discuss changes since the older analyses discussed in
Section 2 ]]
6. Gap analysis
The analysis has shown a certain number of desirable features to be
missing, either in relevant specifications, or in many products.
This section summarizes those gaps.
As noted above, numerous models of various types of product still do
not support IPv6:
CPE
handsets
DSLAMs
routers
traffic management boxes
load balancers
VPN boxes
other appliances
management interfaces and systems
firewalls
accounting and billing systems
It is not the purpose of this document to name and shame vendors, but
it is today becoming urgent for all such products to avoid becoming
part of the IPv4 legacy. ISPs want consistent feature-equal support
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for IPv4 and IPv6 in all equipment and software at reasonable or no
extra cost. The problems can be quite subtle: for example, one CPE
with "full" IPv6 support does not support IPv6 traffic shaping, so
the ISP cannot cap IPv6 traffic to contractual limits. Other needs
and issues mentioned:
o A specific CPE need is an intelligent prefix sub-delegation
mechanism (ease of use issue).
o Full RA support on LAN side of ADSL CPE.
o PPPoE and RADIUS support. Specifically, global unicast address
assignment for L2TP/PPPoE. Currently the PPPoE client will be
assigned a link-local address, requiring a second step (DHCPv6 or
SLAAC).
o Simple automatic distribution of DNS server details is essential;
RFC 5006 support is needed (DNS server option in RA).
o ISPs need fully featured DHCPv6, especially since SLAAC does not
allow settings to be pushed out (except for RFC 5006).
o Firewall systems should not use separate IPv4 and IPv6 rules.
o Customer side firewalls/routers which can do 25-100 Mbit/s.
o Gaps in infrastructure security for IPv6 management.
o Gaps in routers' treatment of header options.
o RA-Guard in switches.
o VRRP support.
o PE-CE routing protocols (OSPF and IS-IS).
o Problems using a single BGP session to exchange routes for both
IPv4 and IPv6.
o IPv6 support in all the best open source tools.
Several ISPs also noted that much commercial applications software
does not correctly support IPv6 and that this will cause customer
problems. Also, some operating systems are still shipped with IPv6
disabled by default, or with features such as IPv4-mapped addresses
disabled by default.
Numerous ISPs clearly want a scaleable NAT64/DNS64 product. Other
protocol-related needs are:
o Getting it right so that a dual stack client doesn't end up trying
to use the wrong transport to reach a site.
o User-side port allocation mechanisms. UPnP IGD and NAT-PMP can be
used for IPv4, but nothing exists for IPv6 (yet). [Editor's
question: since there is no address shortage or port mapping for
IPv6, why is this an issue except in a v4-over-v6 scenarios such
as DS-lite?]
Global IPv6 connectivity still has issues; for example ISPs in the
Pacific region may have to obtain IPv6 transit via the USA (a
situation faced by IPv4 operators in Europe about twenty years ago).
Also, there are persistent PMTUD issues in various places on the net,
and a lack of multicast peering.
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Finally, there was a comment that real deployment case studies must
be shown to operators, along with multihoming and traffic engineering
best practices.
7. Security Considerations
[[ NOTE: this section will be filled out after the previous sections.
]]
8. IANA Considerations
This document makes no request of the IANA.
9. Acknowledgements
We are grateful to all those who answered the questionnaire: Pete
Barnwell, Cameron Byrne, Gareth Campling, David Freedman, Wesley
George, Steinar Haug, Paul Hoogsteder, Mario Iseli, Christian
Jacquenet, Kurt Jaeger, Seiichi Kawamura, Adrian Kennard, Simon
Leinen, Riccardo Loselli, Janos Mohacsi, Jon Morby, Michael Newbery,
Barry O'Donovan, Al Pooley, Antonio Querubin, Anthony Ryan, Marc
Schaeffer, Valeriu Vraciu, Bill Walker and those who preferred to
remain anonymous.
The ISPs willing to be named were: AISP, Alphanet, Breedband Delft,
Claranet, E4A, Fidonet, Finecom, France Telecom, Hungarnet, Imagine,
LavaNet, NEC BIGLOBE, Nepustilnet, Net North West, RoEduNet, SWITCH,
Snap, Sprint, Star Technology, T-Mobile USA, Ventelo, and Whole Ltd.
Useful comments and contributions were also made by Mohamed
Boucadair, and others.
This document was produced using the xml2rfc tool [RFC2629].
10. Change log
draft-carpenter-v6ops-isp-scenarios-01: added summary and discussion
of questionnaire results, 2010-02-23
draft-carpenter-v6ops-isp-scenarios-00: original version, 2009-10-13
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11. Informative References
[I-D.boucadair-port-range]
Boucadair, M., Levis, P., Bajko, G., and T. Savolainen,
"IPv4 Connectivity Access in the Context of IPv4 Address
Exhaustion: Port Range based IP Architecture",
draft-boucadair-port-range-02 (work in progress),
July 2009.
[I-D.ietf-16ng-ip-over-ethernet-over-802-dot-16]
Jeon, H., Riegel, M., and S. Jeong, "Transmission of IP
over Ethernet over IEEE 802.16 Networks",
draft-ietf-16ng-ip-over-ethernet-over-802-dot-16-12 (work
in progress), September 2009.
[I-D.ietf-6man-node-req-bis]
Loughney, J. and T. Narten, "IPv6 Node Requirements RFC
4294-bis", draft-ietf-6man-node-req-bis-03 (work in
progress), July 2009.
[I-D.ietf-v6ops-cpe-simple-security]
Woodyatt, J., "Recommended Simple Security Capabilities in
Customer Premises Equipment for Providing Residential IPv6
Internet Service", draft-ietf-v6ops-cpe-simple-security-09
(work in progress), February 2010.
[I-D.ietf-v6ops-ipv6-cpe-router]
Singh, H., Beebee, W., Donley, C., Stark, B., and O.
Troan, "Basic Requirements for IPv6 Customer Edge
Routers", draft-ietf-v6ops-ipv6-cpe-router-04 (work in
progress), January 2010.
[I-D.ymbk-aplusp]
Bush, R., "The A+P Approach to the IPv4 Address Shortage",
draft-ymbk-aplusp-05 (work in progress), October 2009.
[RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629,
June 1999.
[RFC4029] Lind, M., Ksinant, V., Park, S., Baudot, A., and P.
Savola, "Scenarios and Analysis for Introducing IPv6 into
ISP Networks", RFC 4029, March 2005.
[RFC4294] Loughney, J., "IPv6 Node Requirements", RFC 4294,
April 2006.
[RFC4779] Asadullah, S., Ahmed, A., Popoviciu, C., Savola, P., and
J. Palet, "ISP IPv6 Deployment Scenarios in Broadband
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Access Networks", RFC 4779, January 2007.
[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.
[RFC4942] Davies, E., Krishnan, S., and P. Savola, "IPv6 Transition/
Co-existence Security Considerations", RFC 4942,
September 2007.
[RFC5121] Patil, B., Xia, F., Sarikaya, B., Choi, JH., and S.
Madanapalli, "Transmission of IPv6 via the IPv6
Convergence Sublayer over IEEE 802.16 Networks", RFC 5121,
February 2008.
[RFC5181] Shin, M-K., Han, Y-H., Kim, S-E., and D. Premec, "IPv6
Deployment Scenarios in 802.16 Networks", RFC 5181,
May 2008.
[RFC5211] Curran, J., "An Internet Transition Plan", RFC 5211,
July 2008.
Appendix A. Summary of replies
This summarises the 30 replies received by February 16, 2010. Note
that the answers to some questions do not total to 30, due to missing
answers or to multiple choices in some cases. The ISPs are
distributed as follows:
Europe: 20
North America: 6
Asia/Pacific: 4
They can additionally be classified as:
Commercial: 26
Academic/research: 4
Operating internationally: 5
Operating nationally: 25
Basic data about IP service offerings:
o Offering both origin-only and transit service: 24
o Offering no transit: 6
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o Number of private/small office customers (one IPv4 address): a few
with zero, then from 30 units up to 40 million
o Number of corporate customers (block of IPv4 addresses): a few
with zero, then from 40 units up to 40000
o IP multicast service? 8 yes, 22 no
o Do any customers require multihoming to multiple ISPs? 24 yes, 6
no
o Access technologies used: xDSL, DOCSIS, leased line (X.25, TDM/
PDH, SDH), frame relay, dialup, microwave, FTTP, CDMA, UMTS, LTE,
WiMAX, BWA, WiFi, Ethernet (100M-10G), Ether/MPLS, IPv6-in-IPv4
tunnels
Customer Premises Equipment:
o Do customers use CPE that ISP supplies? 26 yes (20% to 100% of
customers), 4 no
o Does the CPE provided support native IPv6? 16 yes (some), 10 no
o (Note that these numbers include answers that apply to tens of
millions of mobile handsets.)
IPv4 Address Space:
o When do you expect to run out of public IPv4 address space inside
your own network? Estimates run from "now" to 2020, but 4 ISPs
say "never" or "unforeseeable".
o Do you run RFC1918 addresses and NAT within your network? 9 yes;
17 no; 3 others say yes, but only for equipment management or
L3VPN.
o What % of IPv4 space is needed for ISP use (not for customers)? 1%
to 30% (and 100% for NRENs with PI customers).
o When do you expect to run out of public IPv4 address space for
customers? Answers range from 2010 to 2015; 4 ISPs say it depends
on their registry. 3 or 4 give answers suggesting it will never
happen.
o Do you offer RFC1918 addresses to customers? 6 yes, 23 no
IPv6 Requirements:
o Are some big customers requesting IPv6? 18 yes, 12 no
o When do you predict 10% and 50% of customers to require IPv6
service? Ignoring unclear answers, answers for 10% range from
2010 to 2017, and for 50% from 2011 to 2020.
o When do you require IPv6 to be a standard service available to all
customers? Answers range from 2010 to 2015; the most common
answer is 2011.
o When do you predict IPv6 traffic to reach 50% of total traffic?
Answers range from 2011 to 2020; the most common answer is 2015.
IPv6 Status and Plans:
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o Do you currently offer IPv6 as a regular service? 12 yes, 5
partial, 12 no
o What % of customers currently use IPv6? <1% to 30%; mostly 0 or
<1%
o When do you plan to start IPv6 deployment? 11 complete, 12 in
progress, 3 in plan, 4 have no plan
o When do you plan to offer IPv6 as a special or beta-test service?
For all those in progress or with a plan, the answer was either
"now" or during 2010.
o When do you plan to offer IPv6 as a regular service to all
customers? For all those in progress or with a plan, the answer
was between "now" and 2013 (except for one ISP who replied that it
depends on the marketing department).
IPv6 Technologies. Note the answers refer to actual deployment or to
plans, as the case may be:
o Which basic IPv6 access method(s) apply?
* Dual stack routing backbone: 28 yes, 1 maybe
* Separate IPv4 and IPv6 backbones: 2 yes, 1 maybe
* 6to4 relay: 12 yes
* Teredo server: 5 yes
* Tunnel broker: Unfortunately this question was unclear and
obviously misunderstood by most respondents. Several
respondents mentioned that they are getting their own transit
connectivity via static tunnels.
* Something else: Answers were 6VPE + NAT64/DNS64; PNAT;
"considering 6RD"
o Please briefly explain the main reasons/issues behind your choice:
The best summary of the answers is "dual stack is simplest, why do
anything else?".
o Which types of equipment in your network are unable to support
IPv6? The most common answer was CPE (9 mentions). Also
mentioned: handsets; DSLAMs; routers (including several specific
models); traffic management boxes; load balancers; VPN boxes;
management interfaces & systems; firewalls; billing systems.
o Can they be field-upgraded? 5 yes, 4 partially, 10 no and numerous
"don't know" or "hopefully"
o Is any equipment 100% dedicated to IPv6? 7 yes, 23 no
o Is IPv6 an opportunity to restructure your whole topology? 2 yes,
5 partial, 23 no
o Do you include support for DNS AAAA queries over IPv6? 20 yes, 5
plan, 4 no
o Do you include support for reverse DNS for IPv6 addresses? 21 yes,
3 plan, 5 no
o What length(s) of IPv6 prefix do you have or need from the
registry? 1 /19, 1 /21 (plus several /32s), 1 /22 1 /30, 3
multiple /32s, 20 /32, 3 /48
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o What length(s) of IPv6 prefix are offered to customers? 15 ISPs
offer more than one of /48, /52, /56, /60 or /64. 2 offer /56
only, 7 offer /48 only. Two wired operators offer /64 only.
Mobile operators offer /64 in accordance with 3GPP, but at least
one would like to be allowed to offer /128 or /126.
o Do any customers share their IPv6 prefix among multiple hosts?
Unfortunately this question was unclear and obviously
misunderstood by most respondents.
o Do any of your customers prefer to use PI IPv6 prefixes? 9 yes, 17
no
o How are IPv6 prefixes delegated to CPEs? 15 manual, 10
DHCPv6[-PD], 8 SLAAC, 8 RADIUS, 2 PPoE
o Are your SMTP, POP3 and IMAP services dual-stack? 10 yes, 6 plan,
12 no
o Are your HTTP services, including caching and webmail, dual-stack?
9 yes, 1 partial, 4 plan, 14 no
o Are any other services dual-stack? 11 yes, 2 plan, 10 no
o Is each of the following dual-stack?
* Firewalls: 12 yes, 3 partial, 3 plan, 8 no
* Intrusion detection: 10 yes, 2 plan, 12 no
* Address management software: 15 yes, 1 plan, 12 no
* Accounting software: 7 yes, 20 no
* Monitoring software: 16 yes,2 partial,2 plan, 10 no
* Network management tools: 13 yes, 4 partial,1 plan, 10 no
o Do you or will you have IPv6-only customers? 13 yes (or maybe), 17
no (or not likely)
o Do you have customers who have explicitly refused to consider
IPv6? 5 yes, 22 no
o Interworking issues:
* How many years do you expect customers to run any IPv4-only
applications? Answers range from 2 years to infinity, most
frequent answer is >10 years.
* Is IPv6-IPv4 interworking at the the IP layer needed? 15 yes,9
uncertain, 3 no
* Do you include a NAT-PT IPv6/IPv4 translator? 2 yes,1 plan, 25
no
* If yes, does that include DNS translation? 1 plan, 2 no
* If not, do you plan to operate an IPv6/IPv4 translator? 10 plan
(NAT64), 7 no, others uncertain
* If not, how do you plan to connect IPv6-only customers to IPv4-
only services? 7 rely on dual stack; 3 have no plan (one said
"their problem")
* If you offer IP multicast, will that need to be translated too?
1 yes, 2 uncertain, 5 no
o Any plans for Mobile IPv6 (or Nemo mobile networks)? 6 yes,2
uncertain, 21 no
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Appendix B. Questionnaire
This appendix reproduces the technical body of the questionnaire that
was made available for ISPs to express their requirements, plans and
experience.
I. General questions about IP service
1.Do you offer origin-only (stub, end-user) IP service, transit IP
service, or both?
2.Approximate number of private/small office customers (one IPv4
address)
3.Approximate number of corporate customers (block of IPv4
addresses, not included in Q2)
4.Do you offer IP multicast service?
5.Do any of your customers require multihoming to multiple ISPs?
6.Access technologies used (ADSL,etc.)
7.Do your customers use CPE that you supply?
7.1.What % of customers?
7.2.Does the CPE that you provide support native IPv6?
8.When do you expect to run out of public IPv4 address space
inside your own network?
8.1.Do you run private (RFC1918) addresses and NAT within your
network (i.e., a second layer of NAT in the
case of customers with their own NAT)?
8.2.What % of your IPv4 space is needed for your own use (not for
customers)?
9.When do you expect to run out of public IPv4 address space for
customers?
9.1.Do you offer private (RFC1918) addresses to your customers?
II. Questions about requirements for IPv6 service
10.Are some big customers requesting IPv6?
11.When do you predict 10% and 50% of your customers to require
IPv6 service?
12.When do you require IPv6 to be a standard service available to
all customers?
13.When do you predict IPv6 traffic to reach 50% of total traffic?
III. Questions about status and plans for IPv6 service
14.Do you currently offer IPv6 as a regular service?
14.1.What % of your customers currently use IPv6?
14.2.When do you plan to start IPv6 deployment?
14.3.When do you plan to offer IPv6 as a special or beta-test
service to customers?
15.When do you plan to offer IPv6 as a regular service to all
customers?
IV. Questions about IPv6 technologies
16.Which basic IPv6 access method(s) apply:
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16.1. dual stack routing backbone?
16.2. separate IPv4 and IPv6 backbones?
16.3. 6to4 relay?
16.4. Teredo server?
16.5. tunnel broker? If so, which one?
16.6. Something else? Please briefly describe your method:
16.7. If possible, please briefly explain the main reasons/issues
behind your choice.
17.Which types of equipment in your network are unable to support
IPv6?
17.1.Can they be field-upgraded to support IPv6?
17.2.Is any equipment 100% dedicated to IPv6?
18.Is IPv6 an opportunity to restructure your whole topology?
19.Do you include support for DNS AAAA queries over IPv6?
20.Do you include support for reverse DNS for IPv6 addresses?
21.What length(s) of IPv6 prefix do you have or need from the
registry?
22.What length(s) of IPv6 prefix are offered to customers?
22.1.Do any customers share their IPv6 prefix among multiple
hosts?
23.Do any of your customers prefer to use PI IPv6 prefixes instead
of a prefix from you?
24.How are IPv6 prefixes delegated to CPEs? (Manual, PPPoE,
RADIUS, DHCPv6, stateless autoconfiguration/RA, etc...)
25.Are your SMTP, POP3 and IMAP services dual-stack?
26.Are your HTTP services, including caching and webmail, dual-
stack?
27.Are any other services dual-stack?
28.Is each of the following dual-stack?
28.1.Firewalls
28.2.Intrusion detection
28.3.Address management software
28.4.Accounting software
28.5.Monitoring software
28.6.Network management tools
29.Do you or will you have IPv6-only customers?
30.Do you have customers who have explicitly refused to consider
IPv6?
31.How many years do you expect customers to run any IPv4-only
applications?
32.Is IPv6-IPv4 interworking at the the IP layer needed?
33.Do you include a NAT-PT IPv6/IPv4 translator?
33.1.If yes, does that include DNS translation?
33.2.If not, do you plan to operate an IPv6/IPv4 translator?
33.3.If not, how do you plan to connect IPv6-only customers to
IPv4-only services?
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33.4.If you offer IP multicast, will that need to be translated
too?
34.Any plans for Mobile IPv6 (or Nemo mobile networks)?
35.What features and tools are missing today for IPv6 deployment
and operations?
36.Any other comments about your IPv6 experience or plans? What
went well, what was difficult, etc.
Authors' Addresses
Brian Carpenter
Department of Computer Science
University of Auckland
PB 92019
Auckland, 1142
New Zealand
Email: brian.e.carpenter@gmail.com
Sheng Jiang
Huawei Technologies Co., Ltd
KuiKe Building, No.9 Xinxi Rd.,
Shang-Di Information Industry Base, Hai-Dian District, Beijing
P.R. China
Email: shengjiang@huawei.com
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