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APNIC Document identity
Title: IPv6 address allocation and assignment policy
Short title: ipv6-address-policy
Document ref: APNIC-089
Version: 009
Date of original publication: 1 July 2002
Date of this version: 8 November 2010
Review scheduled: n/a
Obsoletes: Previous versions
Status: Active
Comments: n/a
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IPv6 Address Allocation and Assignment Policy
Status of this Memo
This document was initially developed through joint discussions
among the APNIC, ARIN and RIPE communities. The document also
incorporates APNIC-specific policies developed since that time.
Abstract
This document defines registry policies for the assignment and
allocation of globally-unique IPv6 addresses to ISPs and other
organizations. This document obsoletes the "Provisional IPv6
assignment and allocation policy document".
This document was developed jointly by the communities of APNIC,
ARIN, and RIPE.
Contents
1. Introduction
1.1 Overview
2. Definitions
2.1 Internet Registry (IR)
2.2 Regional Internet Registry (RIR)
2.3 National Internet Registry (NIR)
2.4 Local Internet Registry (LIR)
2.5 Allocate
2.6 Assign
2.7 Utilization
2.8 HD-Ratio
2.9 End site
2.10 Internet Exchange Point (IXP)
3. Goals of IPv6 address space management
3.1 Goals
3.2 Uniqueness
3.3 Registration
3.4 Aggregation
3.5 Conservation
3.6 Fairness
3.7 Minimized Overhead
3.8 Conflict of goals
4. IPv6 Policy Principles
4.1 Address space not to be considered property
4.2 Routability not guaranteed
4.3 Minimum Allocation
4.4 Consideration of IPv4 infrastructure
5. Policies for allocations and assignments
5.1 Initial IPv6 block for APNIC members with existing IPv4 space
5.1.1 Criteria
5.1.2 Minimum size of IPv6 block
5.2 Initial allocation
5.2.1 Initial allocation criteria
5.2.2 Minimum initial allocation size
5.2.3 Larger initial allocations
5.3 Subsequent allocation
5.3.1 Subsequent allocation criteria
5.3.2 Applied HD-Ratio
5.3.3 Subsequent Allocation Size
5.4 LIR-to-ISP allocation
5.5 Assignment
5.5.1 Assignment address space size
5.5.2 Assignment of multiple /48s to a single end site
5.5.3 Assignment to operator's infrastructure
5.6 Registration
5.7 Reverse lookup
5.8 Existing IPv6 address space holders
5.9 Portable assignments
5.9.1 Small multihoming assignments
5.9.2 Internet Exchange Points
5.9.3 Critical infrastructure
6. References
7. Appendix A: HD-Ratio
8. Appendix B: Background information
8.1 Background
8.2 Why a joint policy
8.3 The size of IPv6's address space
8.4 Acknowledgment
1. Introduction
1.1 Overview
This document describes policies for the allocation and
assignment of globally-unique Internet Protocol Version 6 (IPv6)
address space. It updates and obsoletes the existing Provisional
IPv6 Policies in effect since 1999 [RIRv6-Policies]. Policies
described in this document are intended to be adopted by each
registry. However, adoption of this document does not preclude
local variations in each region or area.
[RFC2373, RFC2373bis] designate 2000::/3 to be global unicast
address space that IANA may allocate to the RIRs. In accordance
with [RFC2928, RFC2373bis, IAB-Request], IANA has allocated
initial ranges of global unicast IPv6 address space from the
2001::/16 address block to the existing RIRs. This document
concerns the initial and subsequent allocations of the 2000::/3
unicast address space, for which RIRs formulate allocation and
assignment policies.
This policy is considered to be an interim policy. It will be
reviewed in the future, subject to greater experience in the
administration of IPv6.
2. Definitions
[Note: some of these definitions will be replaced by definitions
from other RIR documents in order to be more consistent.]
The following terms and their definitions are of particular
importance to the understanding of the goals, environment, and
policies described in this document.
Responsibility for management of IPv6 address spaces is
distributed globally in accordance with the hierarchical
structure shown below.
Figure 1 Distribution Hierarchy
+--------+
| IANA |
+--------+
|
+-----------+
| |
+--------+ +--------+
| RIR | | RIR | Regional Internet
+--------+ +--------+ Registries (APNIC, ARIN, RIPE NCC,
| | plus possible future RIRs)
| |
| +-----+
| | NIR | National Internet
| +-----+ Registries (AP region)
| |
+--------+ +--------+
|LIR/ISP | |LIR/ISP | Local Internet
+--------+ +--------+ Registries (ISPs)
| |
+--------+ |
| | |
+-------+ +----+ +----+
|EU(ISP)| | EU | | EU | End users
+-------+ +----+ +----+
2.1 Internet Registry (IR)
An Internet Registry (IR) is an organization that is responsible
for distributing IP address space to its members or customers and
for registering those distributions. IRs are classified according
to their primary function and territorial scope within the
hierarchical structure depicted in the figure above.
2.2 Regional Internet Registry (RIR)
Regional Internet Registries (RIRs) are established and
authorized by respective regional communities, and recognized by
the IANA to serve and represent large geographical regions. The
primary role of RIRs is to manage and distribute public Internet
address space within their respective regions.
2.3 National Internet Registry (NIR)
A National Internet Registry (NIR) primarily allocates address
space to its members or constituents, which are generally LIRs
organized at a national level. NIRs exist mostly in the Asia
Pacific region.
2.4 Local Internet Registry (LIR)
A Local Internet Registry (LIR) is an IR that primarily assigns
address space to the users of the network services that it
provides. LIRs are generally ISPs, whose customers are primarily
end users and possibly other ISPs.
2.5 Allocate
To allocate means to distribute address space to IRs for the
purpose of subsequent distribution by them.
2.6 Assign
To assign means to delegate address space to an ISP or end-user,
for specific use within the Internet infrastructure they operate.
Assignments must only be made for specific purposes documented by
specific organizations and are not to be sub-assigned to other
parties.
2.7 Utilization
The actual usage of addresses within each assignment will be
quite low, when compared to IPv4 assignments. In IPv6,
"utilization" is only measured in terms of the bits to the left
of the /56 boundary. In other words, utilization refers to the
assignment of /56s to end sites, and not the number of addresses
assigned within individual /56s at those end sites.
Throughout this document, the term utilization refers to the
allocation of /56s to end sites, and not the number of addresses
assigned within individual /56s within those end sites.
2.8 HD-Ratio
The HD-Ratio is a way of measuring the efficiency of address
assignment [RFC 3194]. It is an adaptation of the H-Ratio
originally defined in [RFC1715] and is expressed as follows:
Log (number of allocated objects)
HD = ------------------------------------------------
Log (maximum number of allocatable objects)
where (in the case of this document) the objects are IPv6 site
addresses (/56s) assigned from an IPv6 prefix of a given size.
2.9 End site
An end site is defined as an end user (subscriber) who has a
business relationship with a service provider that involves:
* that service provider assigning address space to the end user
* that service provider providing transit service for the end
user to other sites
* that service provider carrying the end user's traffic
* that service provider advertising an aggregate prefix route
that contains the end user's assignment
2.10 Internet Exchange Point (IXP)
An Internet Exchange Point (IX or IXP) is a layer 1 and layer 2
network structure that interconnects three or more Autonomous
Systems (AS) for the purpose of Internet traffic interchange.
3. Goals of IPv6 address space management
3.1 Goals
IPv6 address space is a public resource that must be managed in a
prudent manner with regards to the long-term interests of the
internet. Responsible address space management involves balancing
a set of sometimes competing goals. The following are the goals
relevant to IPv6 address policy.
3.2 Uniqueness
Every assignment and/or allocation of address space must
guarantee uniqueness worldwide. This is an absolute requirement
for ensuring that every public host on the Internet can be
uniquely identified.
3.3 Registration
Internet address space must be registered in a registry database
accessible to appropriate members of the Internet community. This
is necessary to ensure the uniqueness of each Internet address
and to provide reference information for Internet troubleshooting
at all levels, ranging from all RIRs and IRs to end users.
The goal of registration should be applied within the context of
reasonable privacy considerations and applicable laws.
3.4 Aggregation
Wherever possible, address space should be distributed in a
hierarchical manner, according to the topology of network
infrastructure. This is necessary to permit the aggregation of
routing information by ISPs, and to limit the expansion of
Internet routing tables.
This goal is particularly important in IPv6 addressing, where the
size of the total address pool creates significant implications
for both internal and external routing.
IPv6 address policies should seek to avoid fragmentation of
address ranges.
Further, RIRs should apply practices that maximize the potential
for subsequent allocations to be made contiguous with past
allocations currently held. However, there can be no guarantee of
contiguous allocation.
In addition, wherever possible, network operators announcing
address space are strongly encouraged to avoid announcing
deaggregated routes when announcing address blocks from a single
Autonomous System unless this deaggregation is required for
traffic engineering purposes.
When contiguous blocks are delegated to a network operator, the
operator is encouraged to announce the contiguous address blocks
as a single aggregated prefix, with minimal additional
announcements of deaggregated prefixes being made only for traffic
engineering requirements.
3.5 Conservation
Although IPv6 provides an extremely large pool of address space,
address policies should avoid unnecessarily wasteful practices.
Requests for address space should be supported by appropriate
documentation and stockpiling of unused addresses should be
avoided.
3.6 Fairness
All policies and practices relating to the use of public address
space should apply fairly and equitably to all existing and
potential members of the Internet community, regardless of their
location, nationality, size or any other factor.
3.7 Minimized Overhead
It is desirable to minimize the overhead associated with
obtaining address space. Overhead includes the need to go back to
RIRs for additional space too frequently, the overhead associated
with managing address space that grows through a number of small
successive incremental expansions rather than through fewer, but
larger, expansions.
3.8 Conflict of goals
The goals described above will often conflict with each other, or
with the needs of individual IRs or end users. All IRs evaluating
requests for allocations and assignments must make judgments,
seeking to balance the needs of the applicant with the needs of
the Internet community as a whole.
In IPv6 address policy, the goal of aggregation is considered to
be the most important.
4. IPv6 Policy Principles
To address the goals described in the previous section, the
policies in this document discuss and follow the basic principles
described below.
4.1 Address space not to be considered property
It is contrary to the goals of this document and is not in the
interests of the Internet community as a whole for address space
to be considered freehold property.
The policies in this document are based upon the understanding
that globally-unique IPv6 unicast address space is licensed for
use rather than owned. Specifically, IP addresses will be
allocated and assigned on a license basis, with licenses subject
to renewal on a periodic basis. The granting of a license is
subject to specific conditions applied at the start or renewal of
the license.
RIRs will generally renew licenses automatically, provided
requesting organizations are making a good-faith effort at
meeting the criteria under which they qualified for or were
granted an allocation or assignment. However, in those cases
where a requesting organization is not using the address space as
intended, or is showing bad faith in following through on the
associated obligation, RIRs reserve the right to not renew the
license.
Note that when a license is renewed, the new license will be
evaluated under and governed by the applicable IPv6 address
policies in place at the time of renewal, which may differ from
the policy in place at the time of the original allocation or
assignment.
4.2 Routability not guaranteed
There is no guarantee that any address allocation or assignment
will be globally routable.
However, RIRs must apply procedures that reduce the possibility
of fragmented address space which may lead to a loss of
routability.
4.3 Minimum Allocation
RIRs will apply a minimum size for IPv6 allocations, to
facilitate prefix-based filtering.
The minimum allocation size for IPv6 address space is /32.
4.4 Consideration of IPv4 infrastructure
Subject to section 5.1.3, existing IPv4 networks may be
considered in determining the initial IPv6 allocation size.
5. Policies for allocations and assignments
5.1 Initial IPv6 block for APNIC members with existing IPv4 space
5.1.1 Criteria
APNIC members that have received an IPv4 address block from APNIC
but have no IPv6 space can qualify for an appropriately sized
IPv6 block under the matching IPv6 policy. For example, a member
that has received an IPv4 IXP assignment will be eligible to
receive an IPv6 IXP assignment.
5.1.2 Minimum size of IPv6 block
The size of the IPv6 delegation for members that meet this
criteria will be based on the following:
* A member that has an IPv4 allocation is eligible for a /32 IPv6
address block.
* A member that has an IPv4 assignment is eligible for a /48 IPv6
address block.
If an APNIC member wishes to receive an initial allocation or
assignment larger than the sizes described above, the member will
need to apply under the alternative criteria described in
sections 5.2 and 5.5 below.
5.2 Initial allocation
5.2.1 Initial allocation criteria
To qualify for an initial allocation of IPv6 address space, an
organization must:
a. Be an LIR
b. Not be an end site
c. Plan to provide IPv6 connectivity to organizations to which it
will make assignments
d. Meet one of the two following criteria:
* Have a plan for making at least 200 assignments to other
organizations within two years OR
* Be an existing LIR with IPv4 allocations from an APNIC or
an NIR, which will make IPv6 assignments or sub-allocations
to other organizations and announce the allocation in the
inter-domain routing system within two years
Private networks (those not connected to the public Internet) may
also be eligible for an IPv6 address space allocation provided
they meet equivalent criteria to those listed above.
5.2.2 Minimum initial allocation size
Organizations that meet the initial allocation criteria are
eligible to receive a minimum allocation of /32.
5.2.3 Larger initial allocations
Initial allocations larger than /32 may be justified if:
1. The organization provides comprehensive documentation of
planned IPv6 infrastructure which would require a larger
allocation; or
2. The organization provides comprehensive documentation of all
of the following:
* its existing IPv4 infrastructure and customer base,
* its intention to provide its existing IPv4 services via
IPv6, and
* its intention to move some of its existing IPv4 customers
to IPv6 within two years.
In either case, an allocation will be made which fulfills the
calculated address requirement, in accordance with the HD-Ratio
based utilization policy.
5.3 Subsequent allocation
Organizations that hold an existing IPv6 allocation may receive a
subsequent allocation in accordance with the following policies.
5.3.1 Subsequent allocation criteria
Subsequent allocation will be provided when an organization
(ISP/LIR) satisfies the evaluation threshold of past address
utilization in terms of the number of sites in units of /56
assignments. The HD-Ratio [RFC 3194] is used to determine the
utilization thresholds that justify the allocation of additional
address as described below.
5.3.2 Applied HD-Ratio
The HD-Ratio value of 0.94 is adopted as indicating an acceptable
address utilization for justifying the allocation of additional
address space. Appendix A provides a table showing the number of
assignments that are necessary to achieve an acceptable
utilization value for a given address block size.
5.3.3 Subsequent allocation size
When an organization has achieved an acceptable utilization for
its allocated address space, it is immediately eligible to obtain
an additional allocation that results in a doubling of the
address space allocated to it. Where possible, the allocation
will be made from an adjacent address block, meaning that its
existing allocation is extended by one bit to the left.
If an organization needs more address space, it must provide
documentation justifying its requirements for a two-year period.
The allocation made will be based on this requirement.
5.4 LIR-to-ISP allocation
There is no specific policy for an organization (LIR) to allocate
address space to subordinate ISPs. Each LIR organization may
develop its own policy for subordinate ISPs to encourage optimum
utilization of the total address block allocated to the LIR.
However, all /48 assignments to end sites are required to be
registered either by the LIR or its subordinate ISPs in such a
way that the RIR/NIR can properly evaluate the HD-Ratio when a
subsequent allocation becomes necessary.
5.5 Assignment
LIRs must make IPv6 assignments in accordance with the following
provisions.
5.5.1 Assignment address space size
End-users are assigned an end site assignment from their LIR or
ISP. The exact size of the assignment is a local decision for the
LIR or ISP to make, using a minimum value of a /64 (when only one
subnet is anticipated for the end site) up to the normal maximum
of /48, except in cases of extra large end sites where a larger
assignment can be justified.
RIRs/NIRs are not concerned about which address size an LIR/ISP
actually assigns. Accordingly, RIRs/NIRs will not request the
detailed information on IPv6 user networks as they did in IPv4,
except for the cases described in Section 4.4 and for the
purposes of measuring utilization as defined in this document.
5.5.2 Assignment of multiple /48s to a single end site
When a single end site requires an additional /48 address block,
it must request the assignment with documentation or materials
that justify the request. Requests for multiple or additional
/48s will be processed and reviewed (i.e., evaluation of
justification) at the RIR/NIR level.
Note: There is no experience at the present time with the
assignment of multiple /48s to the same end site. Having the RIR
review all such assignments is intended to be a temporary measure
until some experience has been gained and some common policies
can be developed. In addition, additional work at defining
policies in this space will likely be carried out in the near
future.
5.5.3 Assignment to operator's infrastructure
An organization (ISP/LIR) may assign a /48 per PoP as the service
infrastructure of an IPv6 service operator. Each assignment to a
PoP is regarded as one assignment regardless of the number of
users using the PoP. A separate assignment can be obtained for
the in-house operations of the operator.
5.6. Registration
When an organization holding an IPv6 address allocation makes
IPv6 address assignments, it must register assignment information
in a database, accessible by RIRs as appropriate (information
registered by an RIR/NIR may be replaced by a distributed
database for registering address management information in
future). Information is registered in units of assigned /48
networks. When more than a /48 is assigned to an organization,
the assigning organization is responsible for ensuring that the
address space is registered in an RIR/NIR database.
RIR/NIRs will use registered data to calculate the HD-Ratio at
the time of application for subsequent allocation and to check
for changes in assignments over time.
IRs shall maintain systems and practices that protect the
security of personal and commercial information that is used in
request evaluation, but which is not required for public
registration.
Organizations that receive an allocation from APNIC can choose
whether or not their customer assignment registrations should be
publicly available. If the organization does not indicate a
choice, or it chooses to hide its customer assignment
registrations, then those records will not be visible in the
public whois database. Whois queries on these records will return
details of the allocation.
In addition, it is mandatory to register an Incident Report Team
(IRT) object for each allocation and assignment record in the APNIC
Whois Database.
5.7. Reverse lookup
When an RIR/NIR delegates IPv6 address space to an organization,
it also delegates the responsibility to manage the reverse lookup
zone that corresponds to the allocated IPv6 address space. Each
organization should properly manage its reverse lookup zone. When
making an address assignment, the organization must delegate to
an assignee organization, upon request, the responsibility to
manage the reverse lookup zone that corresponds to the assigned
address.
5.8 Existing IPv6 address space holders
Organizations that received /35 IPv6 allocations under the
previous IPv6 address policy [RIRv6-Policies] are immediately
entitled to have their allocation expanded to a /32 address
block, without providing justification, so long as they satisfy
the criteria in Section 5.1.1. The /32 address block will contain
the already allocated smaller address block (one or multiple /35
address blocks in many cases) that was already reserved by the
RIR for a subsequent allocation to the organization. Requests for
additional space beyond the minimum /32 size will be evaluated as
discussed elsewhere in the document.
5.9 Portable assignments
5.9.1 Small multihoming assignments
An organization is eligible to receive a portable assignment from
APNIC if it is currently multihomed or plans to be multihomed
within three months.
An organization is considered to be multihomed if its network
receives full-time connectivity from more than one ISP and has
one or more routing prefixes announced by at least two of its
ISPs.
The minimum assignment made under these terms is /48.
Address space assigned under these terms and not used for
multihoming three months after assignment by APNIC will be
reclaimed.
5.9.2 Internet Exchange Points
Internet Exchange Points are eligible to receive a portable
assignment from APNIC to be used exclusively to connect the IXP
participant devices to the Exchange Point.
The minimum assignment made under these terms is /48.
Global routability of the portable assignment is left to the
discretion of the IXP and its participants.
5.9.3 Critical infrastructure
The following critical infrastructure networks, if operating in
the Asia Pacific region, are eligible to receive a portable
assignment:
* root domain name system (DNS) server;
* global top level domain (gTLD) nameservers;
* country code TLD (ccTLDs) nameservers;
* IANA;
* Regional Internet Registry (RIRs); and
* National Internet Registry (NIRs).
Assignments to critical infrastructure are available only to the
actual operators of the network infrastructure performing such
functions. Registrar organizations which do not actually host the
network housing the registry infrastructure, will not be eligible
for an assignment under this policy.
The maximum assignment made under these terms is /32 per
operator.
Exchanges made under this policy remain subject to the address
space license policy.
6. References
[RFC1715] "The H Ratio for Address Assignment Efficiency", C.
Huitema. November 1994, RFC 1715.
[IAB-Request] "Email from IAB to IANA",
http://www.iab.org/iab/DOCUMENTS/IPv6addressspace.txt.
[RFC2373] "IP Version 6 Addressing Architecture", R. Hinden, S.
Deering. July 1998, RFC 2373.
[RFC2373bis] draft-ietf-ipngwg-addr-arch-v3-07.txt.
[RFC2928] "Initial IPv6 Sub-TLA ID Assignments", R. Hinden, S.
Deering, R. Fink, T. Hain. September 2000, RFC 2928.
[RFC3177] "IAB/IESG Recommendations on IPv6 Address". IAB, IESG.
September 2001, RFC 3177.
[RFC3194] "The H-Density Ratio for Address Assignment Efficiency
An Update on the H ratio", A. Durand, C. Huitema. November 2001,
RFC 3194.
[RIRs-on-48]
http://www.arin.net/library/guidelines/ipv6_initial.html,
[RIRv6-Policies]
http://www.arin.net/regserv/ipv6/ipv6guidelines.html,
http://www.ripe.net/ripe/docs/ripe-196.html,
http://archive.apnic.net/docs/drafts/ipv6/ipv6-policy-
280599.html.
7. Appendix A: HD-Ratio
The utilization threshold T, expressed as a number of individual
/56 prefixes to be allocated from IPv6 prefix P, can be
calculated as:
T=2((56-P)*HD)
Thus, the utilization threshold for an organization requesting
subsequent allocation of IPv6 address block is specified as a
function of the prefix size and target HD ratio. This utilization
refers to the allocation of /56s to end sites, and not the
utilization of those /56s within those end sites. It is an
address allocation utilization ratio and not an address
assignment utilization ratio.
This document adopts an HD-Ratio of 0.94 as the utilization
threshold for IPv6 address space allocations.
The following table provides equivalent absolute and percentage
address utilization figures for IPv6 prefixes, corresponding to
an HD-Ratio of 0.94
P 56-P Total /56s Threshold Util %
56 0 1 1 100.0
55 1 2 2 95.9
54 2 4 4 92.0
53 3 8 7 88.3
52 4 16 14 84.7
51 5 32 26 81.2
50 6 64 50 77.9
49 7 128 96 74.7
48 8 256 184 71.7
47 9 512 352 68.8
46 10 1,024 676 66.0
45 11 2,048 1,296 63.3
44 12 4,096 2,487 60.7
43 13 8,192 4,771 58.2
42 14 16,384 9,153 55.9
41 15 32,768 17,560 53.6
40 16 65,536 33,689 51.4
39 17 131,072 64,634 49.3
38 18 262,144 124,002 47.3
37 19 524,288 237,901 45.4
36 20 1,048,576 456,419 43.5
35 21 2,097,152 875,653 41.8
34 22 4,194,304 1,679,965 40.1
33 23 8,388,608 3,223,061 38.4
32 24 16,777,216 6,183,533 36.9
31 25 33,554,432 11,863,283 35.4
30 26 67,108,864 22,760,044 33.9
29 27 134,217,728 43,665,787 32.5
28 28 268,435,456 83,774,045 31.2
27 29 536,870,912 160,722,871 29.9
26 30 1,073,741,824 308,351,367 28.7
25 31 2,147,483,648 591,580,804 27.5
24 32 4,294,967,296 1,134,964,479 26.4
23 33 8,589,934,592 2,177,461,403 25.3
22 34 17,179,869,184 4,177,521,189 24.3
21 35 34,359,738,368 8,014,692,369 23.3
20 36 68,719,476,736 15,376,413,635 22.4
19 37 137,438,953,472 29,500,083,768 21.5
18 38 274,877,906,944 56,596,743,751 20.6
17 39 549,755,813,888 108,582,451,102 19.8
16 40 1,099,511,627,776 208,318,498,661 18.9
15 41 2,199,023,255,552 399,664,922,315 18.2
14 42 4,398,046,511,104 766,768,439,460 17.4
13 43 8,796,093,022,208 1,471,066,903,609 16.7
12 44 17,592,186,044,416 2,822,283,395,519 16.0
11 45 35,184,372,088,832 5,414,630,391,777 15.4
10 46 70,368,744,177,664 10,388,121,308,479 14.8
9 47 140,737,488,355,328 19,929,904,076,845 14.2
8 48 281,474,976,710,656 38,236,083,765,023 13.6
7 49 562,949,953,421,312 73,357,006,438,603 13.0
6 50 1,125,899,906,842,620 140,737,488,355,328 12.5
5 51 2,251,799,813,685,250 270,008,845,646,446 12.0
4 52 4,503,599,627,370,500 518,019,595,058,136 11.5
8. Appendix B: Background information
8.1 Background
The impetus for revising the 1999 Provisional IPv6 policy started
with the APNIC meeting held in Taiwan in August 2001. Follow-on
discussions were held at the October, 2001 RIPE and ARIN
meetings. During these meetings, the participants recognized an
urgent need for more detailed, complete policies. One result of
the meetings was the establishment of a single mailing list to
discuss a revised policy together with a desire to develop a
general policy that all RIRs could use. This document does not
provide details of individual discussions that lead to policies
described in this document; detailed information can be found in
the individual meeting minutes at the www.apnic.net,
www.arin.net, and www.ripe.net web sites.
8.2 Why a joint policy
IPv6 addresses are a public resource that must be managed with
consideration to the long-term interests of the internet
community. Although regional registries adopt allocation policies
according to their own internal processes, address policies
should largely be uniform across registries. Having significantly
varying policies in different regions is undesirable because it
can lead to situations where "registry shopping" can occur as
requesting organizations request addresses from the registry that
has the most favorable policy for their particular desires. This
can lead to the policies in one region undermining the efforts of
registries in other regions with regards to prudent stewardship
of the address space. In cases where regional variations from the
policy are deemed necessary, the preferred approach is to raise
the issue in the other regional registries in order to develop a
consensus approach that all registries can support.
8.3 The size of IPv6's address space
It should be noted that the 128-bit address space is divided into
three logical parts, with the usage of each component managed
differently. The rightmost 64 bits, the Interface Identifier
[RFC2373], will often be a globally-unique IEEE identifier (e.g.,
mac address). Although an "inefficient" way to use the Interface
Identifier field from the perspective of maximizing the number of
addressable nodes, the numbering scheme was explicitly chosen to
simplify Stateless Address Autoconfiguration [RFC2462]. The
middle bits of an address indicate the subnet ID.
8.4 Acknowledgment
The initial version of this document was produced by The JPNIC
IPv6 policy drafting team consisting of Akihiro Inomata, Akinori
Maemura, Kosuke Ito, Kuniaki Kondo, Takashi Arano, Tomohiro
Fujisaki, and Toshiyuki Yamasaki. Special thanks goes out to this
team, who worked over a holiday in order to produce an initial
document quickly.
An editing team was then organized by representatives from each
of the three RIRs (Takashi Arano, Chair of APNIC's Policy SIG,
Thomas Narten, Chair of ARIN's IPv6 WG, and David Kessens, Chair
of RIPE NCC's IPv6 WG).
The editing team would like to acknowledge the contributions to
this document of Takashi Arano, John Crain, Steve Deering, Gert
Doering, Kosuke Ito, Richard Jimmerson, David Kessens, Mirjam
Kuehne, Anne Lord, Jun Murai, Paul Mylotte, Thomas Narten, Ray
Plzak, Dave Pratt, Stuart Prevost, Barbara Roseman, Gerard Ross,
Paul Wilson, Cathy Wittbrodt and Wilfried Woeber.
The final editing of the initial document was done by Thomas
Narten.