Global Standardization Activities

IPv6 Technical Issues—Standardization,
Resource Management, and Operation
Tomohiro Fujisaki† and Shiro Niinobe
Abstract
With IPv6 (Internet protocol version 6) being widely used not only as a protocol for accessing theInternet but also as a base for many IP-based services, it is becoming an essential element of networking services. This article describes the current situation of IPv6 from the viewpoints of standardization
in IETF (Internet Engineering Task Force), IPv6 address allocation status as part of Internet resource
management, and operation of the IPv6 network.

1. Introduction
The Internet has been growing along three axes:
standardization, resource management, and operation. The IETF (Internet Engineering Task Force) has
been standardizing the technology, and regional
Internet registries (RIRs) have been managing Internet resources such as IP (Internet protocol) addresses(both IPv4 and IPv6) and autonomous system numbers. Moreover, network operators’ groups such as
NANOG (The North American Network Operators’Group) and JANOG (Japan Network Operators’Group) have discussed operational issues about theInternet. Although IPv6 has been subject to standardization for some time, after RIRs began to allocate
IPv6 address to organizations such as Internet serviceproviders (ISPs), discussions of IPv6 address allocation and assignment policy became active. At thesame time, operators’ groups also began to discuss
operational issues concerning IPv6 networks.
2. Standardization of IPv6 technology
In the IETF, ipng wg (IP Next Generation WorkingGroup) and ngtrans wg (Next Generation Transition
Working Group) have standardized IPv6 technology
such as IPv6 protocol itself and transition functions
for migrating from the current Internet. During the† NTT Information Sharing Platform Laboratories
Musashino-shi, 180-8585 Japan
E-mail: fujisaki.tomohiro@lab.ntt.co.jp

50

standardization, ipng wg changed its name to ipv6wg, and ngtrans wg handed over operational topics tov6ops wg (IPv6 Operations Working Group) and disbanded. IPv6-related topics have been discussed inmany working groups recently, since the IETF mandated protocol-independent standardization (standardized protocols should work on both IPv4 andIPv6) when Internet-related protocols are discussed.
The changes in the IPv6-related working groups in
the IETF are shown in Fig. 1.
3. Current status of ipv6 wg
The ipv6 wg decided that the wg meeting held in
Vancouver in November 2005 was the last face-toface meeting in the IETF, and they will disband after
finishing current working items in order to show theworld that IPv6 standardization has finished. One ofthe main remaining items is to move the IPv6 basespecification RFCs (Requests for Comments: protocol specification documents in the IETF) to the finalstate. The target RFCs are: RFC2460, “Internet Protocol, Version 6 Specification”; RFC2461, “Neighbor
Discovery for IP Version 6”; RFC2462, “IPv6 Stateless Address Autoconfiguration”; and RFC2463,“Internet Control Message Protocol (ICMPv6) for theInternet Protocol Version 6 (IPv6) Specification”.
Currently, these RFCs are in the ‘Draft Standard’
state, which is the stage before the final ‘Standard’state. The standardization process in IETF is shownin Fig. 2. Over 4400 RFCs have been issued, but only
66 are in the final ‘Standard’ state (e.g., IP, TCP
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Global Standardization Activities

1994

ipng wg

IPv6 base specification
Constructing 6bone(IPv6 experimental network)

1996

ngtrans wg

1997

IPv6 deployment (IPv4/IPv6
coexistence and transition)
2002

ipv6 wg

v6ops wg

Recently, IPv6-related topics have been
discussed in almost all IETF wgs.
2005
Face-to-facemeetings finishedFig. 1. Changes in IPv6-related working groups in IETF.

Internet draft
Best current practiceExperimental

Informational
Proposed Standard

Draft Standard

Standard

Standard track

Only 66 RFCs are inthe ‘Standard’ state(as of Apr. 1, 2006)
e.g., IP(v4), UDP,and TCP.

Historic

RFC

Fig. 2. Standardization process in IETF.

(transmission control protocol), and UDP (user datagram protocol)). Many protocols that are currently
used are actually still in the ‘Proposed Standard’ or‘Draft Standard’ state.
4. Trend of the Internet resource management
communities
RIRs began to allocate IPv6 addresses in 1999, andtoday, many organizations have IPv6 address blocks.
The changes in the numbers of organizations receiving addresses over time is shown in Fig. 3. RIRs allocate IPv6 addresses under almost the same address
allocation and assignment policies [1]. The basis ofVol. 4 No. 7 July 2006

this policy was drafted by Japanese volunteers andwent into effect as a world-wide policy in July 2002.
The original IPv6 policy has been modified slightly in each region to reflect the local situation, such as
IPv6 deployment status. Address policy modifications of this kind are performed in a bottom-up manner in each RIR. There are five RIRs: ARIN (American Registry for Internet Numbers) in charge ofNorth America, RIPE-NCC (Resource IP Europeans
Network Coordination Centre) in Europe, APNIC(Asia Pacific Network Information Centre), LACNIC(Latin American and Caribbean Internet AddressRegistry), and AfriNIC (Africa Network InformationCentre). APNIC, for example, holds open policy
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Global Standardization Activities

1200

Number of organizations

1000
800

ARIN
RIPE-NCCAPNIC
LACNIC
Total

600
40020001999

2000

2001

2002

2003

2004

2005

topics are:- Practical operational issues, e.g.,
how to filter IPv6 packets to protect the IPv6 network.
- IP-infrastructure-related issues,e.g., the DNS (domain name system) will require higher performance when IPv6-enabledmachines become common
because they will issue more thantwice as many DNS queries (i.e., inboth IPv4 and IPv6).
5. Conclusion

YearNTT Information Sharing Platform
Laboratories has tackled Internetrelated problems on all three axes by promoting standardization in the IETF, proposing address policies in
its RIR, and discussing network operational issues inNANOG and JANOG. We will continue to cope with
IPv6-related problems raised by NTT’s network andcontribute to the deployment of IPv6.

Fig. 3. Changes in numbers of IPv6 address holders.

meetings twice a year, and people who want to modify or create a policy make a proposal at that meeting.
Once the proposed policy reaches a consensus in thecommunity, it is implemented by APNIC and goes
into effect in the Asia Pacific Region.
The following IPv6 address policy issues have been
discussed recently in APNIC.
- Changing IPv6 address allocation and assignment
size
Some people estimate that under the current IPv6
address allocation criteria, IPv6 addresses will beexhausted in 60 years. To increase the lifetime ofIPv6, they propose using stricter address allocation
criteria.
- IPv6 portable assignment for multihoming
The person making this proposal said that IPv6
will be used in mission critical systems and that
reliability will become more and more necessary.
To achieve the same level of reliability as IPv4,
IPv6 will require BGP-based multihoming andportable IPv6 addresses should be assigned to end
sites (BGP: border gateway protocol).
Policy proposals for Internet resource managementin the Asia Pacific region are available online [2].
5. Discussions in operators’ communities
Discussions in network operators’ communities
such as NANOG and JANOG mainly concern practical operational topics, which are based on the IPv4
Internet. However, some IPv6-related topics havebegun to be discussed recently. In JANOG in particular, there has been continuous discussion of IPv6
operational issues in recent meetings. This is because
IPv6 has become popular in Japan. The discussion
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References[1][2]

http://www.apnic.net/docs/policy/ipv6-address-policy.html
http://www.apnic.net/docs/policy/proposals/index.html

Tomohiro Fujisaki
Senior Research Engineer, Supervisor, Ubiquitous Computing Project, NTT Information Sharing Platform Laboratories.
He received the B.E. and M.E. in information
science from Tokyo Institute of Technology,
Tokyo, in 1988 and 1990, respectively. In 1990,
he joined NTT Software Laboratories, Tokyo.
He has been studying IPv6 networking technology since 1997 and his current research subject is
operation and management of the IPv6 network.
He has been co-chair of the IPv6 technical SIG ofAPNIC since 2005. He is a member of the Information Processing Society of Japan and theAssociation for Computing Machinery.

Shiro Niinobe
Research Engineer, Ubiquitous Computing
Project, NTT Information Sharing Platform Laboratories.
He joined NTT Electrical Communication
Laboratories, Tokyo, in 1985. In 2005, he moved
to NTT Information Sharing Platform Laboratories to study IPv6 networking technology. His
current research subject is operation and management of the IPv6 network.

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