[ppml] Proposed Policy: IPv4 Micro-allocations for anycast services

Azinger, Marla marla_azinger at eli.net
Thu Aug 11 12:30:23 EDT 2005

David, here are my questions and comments~

1. I assume their is a routing reason behind this but just so everyone is clear, can you provide the reasoning behind the decision to make these allocations come from a "reserved block"?

2. Does this policy really help anything by allowing /24's as a microallocation if you are sincere with the statement below?  Or am I misinterpreting it?  Or is this part of a routing rational?
	"As many ISPs also filter routes longer than /22, it is
	impractical to use a longer mask for any netblock that is utilized for
	an anycast service."

Thank you for your time
Marla Azinger
Electric Lightwave
Frontier Communications
IP Engineer

-----Original Message-----
From: ppml-bounces at arin.net [mailto:ppml-bounces at arin.net]On Behalf Of
Member Services
Sent: Wednesday, August 10, 2005 8:30 AM
To: ppml at arin.net
Subject: [ppml] Proposed Policy: IPv4 Micro-allocations for anycast

ARIN received the following proposed policy. In accordance with the ARIN
Internet Resource Policy Evaluation Process, the proposal is being
posted to the ARIN Public Policy Mailing List and being placed on ARIN's

The ARIN Advisory Council (AC) will review the proposal and within ten
working days may decide to:
1)  Support the proposal as is,
2)  Work with the author to clarify, divide or combine one or more
policy proposals, or
3)  Not support the policy proposal.

If the AC supports the proposal or reaches an agreement to work with the
author, then the proposal will be posted as a formal policy proposal to
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may elect to use the petition process to advance the proposal. If the
author elects not to petition or the petition fails, then the proposed
policy will be considered closed.

The ARIN Internet Resource Policy Evaluation Process can be found at:

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Member Services
American Registry for Internet Numbers (ARIN)

### * ###

Policy Proposal Name: IPv4 Micro-allocations for anycast services

Author: David Williamson

Policy term: permanent

Policy statement:

In the NRPM IPv4 section, renumber 4.4 to 4.4.1, and add:

4.4.2 Micro-allocations for anycast services - ARIN will make
micro-allocations to organizations wishing to deploy anycast based
services, provided they meet the following criteria:

     * All of the criteria normally required to receive IPv4 space, AND
     * The organization must have multiple (at least two) discrete
	multi-homed networks.
     * The organization must identify which networks, ASNs, or sites
	will host the new service.
     * The organization must provide a description of the anycast service.

Micro-allocations for anycast services will be no longer than a /24.
These allocations will be made out of blocks reserved for
micro-allocation purposes.  ISPs and other organizations receiving these
micro-allocations will be charged under the ISP fee schedule, while
end-users will be charged under the fee schedule for end-users.


There are an increasing number of anycast-based applications being
offered by service providers and other organizations.  Indeed, many
basic infrastructure services (like the DNS root servers) are already
anycast based.  (See RFC 1546 for an authoritative discussion of anycast

Deployment of new services is hampered, however, by current IPv4
allocation policies.  For organizations that do not have legacy IP
space, justifying a /22 to serve a handful of addresses is effectively
impossible.  As many ISPs also filter routes longer than /22, it is
impractical to use a longer mask for any netblock that is utilized for
an anycast service.  This situation is also generally unfavorable to
younger organizations, while giving older organizations that do have a
surplus of legacy space a competitive advantage.

In light of this, some organizations may simply lie about their
addressing needs in order to convince an RIR that a /22 is required,
when a much smaller network would suffice.  This is not a behavior that
should be encouraged by policy.

The obvious answer is that a micro-allocation scheme needs to be created
to allow organizations deploying anycast services to acquire a network
of more appropriate size.

It is also clear that a micro-allocation policy that makes it easier for
organizations to acquire small netblocks may lead to additional improper
allocations to organizations that simply wish to acquire additional
small blocks of space.  This policy proposal attempts to address that by
requiring more stringent requirements for such allocations.

Timetable for implementation: immediate

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