ARIN-PPML Message

[arin-ppml] 2010-8: Rework of IPv6 assignment criteria

Draft Policy 2010-8
Rework of IPv6 assignment criteria

Attached is the ARIN staff assessment of the revised 2010-8.

This draft policy is open for discussion on this mailing list and will
be on the agenda at the upcoming ARIN Public Policy Meeting in Atlanta.

2010-8 is below and available at:
https://www.arin.net/policy/proposals/2010_8.html

Regards,

Communications and Member Services
American Registry for Internet Numbers (ARIN)


## * ##


Staff Assessment of Draft Policy 2010-8 (version dated 14 September 2010)
Rework of IPv6 assignment criteria

1. Proposal Summary (Staff Understanding)

This policy replaces the existing IPv6 assignment policy established in
NRPM 6.5.8. It establishes four optional criteria for qualifying for an
initial IPv6 assignment and provides criteria for requests larger than
the default /48, and for subsequent assignments. Additional changes
include the replacement of the HD ratio as the standard utilization
metric with a utilization percentage; the elimination of the requirement
that ARIN reserve adjacent space when making v6 assignments; and changes
to the initial and subsequent assignment sizes. Finally, it encourages
organizations to aggregate any non-contiguous direct assignments they have.

2. Comments

A. ARIN Staff Comments

· This policy requires staff to automatically issue a /40 for networks
with 12-192 sites. A /40 is the point at which the fee schedule jumps to
the small fee. So, an org that formerly could request a smaller block (a
/42 for example), which would have been an x-small block with a $1,250
fee, must now get a /40 and pay the higher fee of $2,250.

· Staff finds the policy text in the following sections to be unclear
and confusing, which makes it difficult for staff to implement. If the
text were to be simplified and written in a more straightforward manner,
it would become more understandable, and therefore more likely to be
utilized by the community.

   o Section 6.5.8.2.1 "Where a site is a discrete location that is
part of an organization’s network." This seems out of context to both
of the adjacent sentences and we aren’t sure how it applies.

   o Section 6.5.8.2.2 "An extra-large site will receive the
smallest prefix such that the total subnet utilization justified does
not exceed 25%."

   o Section 6.5.8.2.3 "More than 3,072 sites justified, receives a /32
assignment or larger. In cases where more than 3,072 sites are
justified, an assignment of the smallest prefix, aligned on a nibble
boundary, will be made such that the total utilization based on the
number of sites justified above does not exceed 75%."

   o Section 6.5.8.3 "A subsequent assignment is justified when the
total utilization based on the number of sites justified exceeds 75%
across all of an organization’s assignments"

· It seems inconsistent to have the end-user IPv6 policy use utilization
percentage while the ISP IPv6 policy uses HD ratio to measure utilization.

B. ARIN General Counsel

This proposal poses no significant legal issues.

3. Resource Impact

This policy would have minimal resource impact. It is estimated that
implementation would occur within 3 months after ratification by the
ARIN Board of Trustees. The following would be needed in order to implement:

    * Updated guidelines
    * Staff training

Full draft policy text below:

> Draft Policy 2010-8

> Rework of IPv6 assignment criteria

> Date: 9/14/2010

> Policy statement:

> Replace section 6.5.8 as follows;

>

> 6.5.8. Direct assignments from ARIN to end-user organizations

>

> 6.5.8.1 Initial Assignment Criteria

>

> Organizations may justify an initial assignment for addressing devices

> directly attached to their own network infrastructure, with an intent

> for the addresses to begin operational use within 12 months, by meeting

> one of the following criteria:

>

> a. Having a previously justified IPv4 end-user assignment from ARIN or

> one of its predecessor registries, or;

>

> b. Currently being IPv6 Multihomed or immediately becoming IPv6

> Multihomed and using an assigned valid global AS number, or;

>

> c. By having a network consisting of a total of 1000 or more hosts, or;

>

> d. By providing a reasonable technical justification indicating why

> IPv6

> addresses from an ISP or other LIR are unsuitable.

>

> Examples of justifications for why addresses from an ISP or other LIR

> may be unsuitable include, but are not limited to:

>

> • An organization that operates infrastructure critical to life safety

> or the functioning of society can justify the need for an assignment

> based on the fact that renumbering would have a broader than expected

> impact than simply the number of hosts directly involved. These would

> include: hospitals, fire fighting, police, emergency response, power or

> energy distribution, water or waste treatment, traffic management and

> control, etc…

> • Regardless of the number of hosts directly involved, an organization

> can justify the need for an assignment if renumbering would affect 1000

> or more individuals either internal or external to the organization.

> • An organization with a network not connected to the Internet can

> justify the need for an assignment by documenting a need for guaranteed

> uniqueness, beyond the statistical uniqueness provided by ULA (see RFC

> 4193).

> • An organization with a network not connected to the Internet, such as

> a VPN overlay network, can justify the need for an assignment if they

> require authoritative delegation of reverse DNS.

>

> 6.5.8.2 Initial assignment size

>

> Organizations that meet at least one of the initial assignment criteria

> above are eligible to receive an initial assignment of /48. Requests

> for

> larger initial assignments, reasonably justified with supporting

> documentation, will be evaluated based on the number of sites in an

> organization’s network and the number of subnets needed to support any

> extra-large sites defined below.

>

> 6.5.8.2.1 /48 per site

>

> An organization may request up to a /48 for each site in its network,

> including any sites that will be operational within 12 months. Where a

> site is a discrete location that is part of an organization’s network.

> In the case of a multi-tenant building, each organization located at

> the

> site may separately justify a /48 for its network at the site.

>

> A campus with multiple buildings may be considered as one or multiple

> sites, based on the implementation of its network infrastructure. For

> a

> campus to be considered as multiple sites, reasonable technical

> documentation must be submitted describing how the network

> infrastructure is implemented in a manner equivalent to multiple sites.

>

> 6.5.8.2.2 Extra-large site

>

> In rare cases, an organization may request more than a /48 for an

> extra-large site which requires more than 16,384 /64 subnets. In such

> a

> case, a detailed subnet plan must be submitted for each extra-large

> site

> in an organization’s network. An extra-large site will receive the

> smallest prefix such that the total subnet utilization justified does

> not exceed 25%. Each extra-large site will be counted as an equivalent

> number of /48 sites.

>

> 6.5.8.2.3 Larger initial assignments

>

> Larger initial assignments will be determined based on the number of

> sites justified above, aligned on a nibble boundary using the following

> table:

>

> More than 1 but less than or equal to 12 sites justified, receives a

> /44

> assignment;

> More than 12 but less than or equal to 192 /sites justified, receives a

> /40 assignment;

> More than 192 but less than or equal to 3,072 sites justified, receives

> a /36 assignment;

> More than 3,072 sites justified, receives a /32 assignment or larger.

>

> In cases where more than 3,072 sites are justified, an assignment of

> the

> smallest prefix, aligned on a nibble boundary, will be made such that

> the total utilization based on the number of sites justified above does

> not exceed 75%.

>

> 6.5.8.3 Subsequent assignments

>

> Requests for subsequent assignments with supporting documentation will

> be evaluated based on the same criteria as an initial assignment under

> 6.5.8.2 with the following modifications:

>

> a. A subsequent assignment is justified when the total utilization

> based

> on the number of sites justified exceeds 75% across all of an

> organization’s assignments. Except, if the organization received an

> assignment per section 6.11 IPv6 Multiple Discrete Networks, such

> assignments will be evaluated as if it were to a separate organization.

>

> Organizations may have multiple separate assignments that should be

> considered in total, due to previous subsequent assignments made per

> clause 6.5.8.3.c below, or through Mergers and Acquisitions in section

> 8.2.

>

> b. When possible subsequent assignments will result it the expansion of

> an existing assignment by one or more nibble boundaries as justified.

>

> c. If it is not possible to expand an existing assignment, or to expand

> it adequately to meet the justified need, then a separate new

> assignment

> will be made of a size as justified.

>

> 6.5.8.4 Consolidation and return of separate assignments

>

> Organizations with multiple separate assignments should consolidate

> into

> a single aggregate, if feasible. If an organization stops using one or

> more of its separate assignments, any unused assignments must be

> returned to ARIN.

>

> Rationale:

>

> This proposal provides a complete rework of the IPv6 end-user

> assignment

> criteria, removing the dependency on IPv4 policy, providing clear

> guidance in requesting larger initial assignments, and eliminating

> HD-Ratio as criteria for evaluating end-user assignments.

>

> The HD-Ratio is replaced with a simplified 75% utilization threshold

> based on nibble boundaries for end-user assignments. This threshold

> is

> somewhat more restrictive for larger assignments, while slightly less

> restrictive for the smaller /44 assignments, than the HD-Ratio.

> However, in both cases it is much easier for an end-user to understand

> the policy criteria that applies to them.

>

> The following general concepts are included:

>

> • Previously justified IPv4 resources may be used to justify the need

> for IPv6 resources

> • Internet multihoming is sufficient justification for an IPv6 end-user

> assignment in and of itself

> • Networks with more than 1000 hosts have a justified need for IPv6

> resources; as is the case in current policy, it is just more clearly

> stated without relying on a reference to, and the consequences of, IPv4

> policy

> • Other end-users must justify why an ISP or LIR assignment is not

> sufficient for their needs

> • Organizations with multiple sites may receive a /48 for each site in

> their network

> • A campus with multiple buildings may be considered as one or multiple

> sites, based on the implementation of its network infrastructure

> • Reservations are no longer necessary as ARIN has committed to sparse

> assignment for IPv6

> • Providing sufficiently large initial assignments based on nibble

> boundaries along with sparse assignments will reduce route table growth

> caused solely by subsequent assignments

>

> The 25% subnet utilization for an extra-large site is proposed as the

> threshold for a larger prefix in order to allow an extra-large site

> enough room to create an organized subnet plan. Requiring denser usage

> would make it almost impossible for an extra-large site to maintain any

> kind of organized subnet plan. Furthermore, even at 25% utilization,

> more than 16,384 subnets are required to justify more than a /48 for a

> site. Few, if any, sites can actually meet or exceed this threshold.

>

> The ARIN Board of Trusties should consider incentives that provide

> additional motivation for end-users to consolidate into a single

> aggregate per section 6.5.8.4 of this policy.

>

> Timetable for implementation: Immediate