[ARIN-Suggestions] Response to ACSP 2017.14: Provide Statistics About the Size of Available 2-byte and 4-byte ASNs

ARIN info at arin.net
Mon Aug 7 16:08:33 EDT 2017

Today ARIN issued its response to ACSP 2017.14: Provide Statistics About 
the Size of Available 2-byte and 4-byte ASNs. The full text of the 
suggestion is available at: 


Thank you for your suggestion, numbered 2017.14 upon confirmed receipt,
to provide statistics about the size of ARIN's available 2-byte and
4-byte AS number pools.

As guided by previous policy in the Number Resource Policy Manual
(NRPM), ARIN no longer makes a distinction between 2-byte only and
4-byte only AS numbers, but does recognize identification of the
"classic 2-byte range" of AS numbers sometimes referred to by customers
during the request process. For the purposes of this ACSP response, AS
numbers from the classic 2-byte pool will be referred to as "2-byte" and
those from the non-classic, 2-byte pool will be referred to as "4-byte".
At the time of writing this ACSP response, ARIN has 303 2-byte AS
numbers along with 677 4-byte AS numbers in our active inventory to be
issued. Newly approved requests receive the lowest AS number in our
active inventory at the time of issuance. If we happen to have a 2-byte
AS number in inventory at that time, it will be issued. In cases where
there is no 2-byte AS number in active inventory at the time of
issuance, the next 4-byte AS number in the inventory is issued.

ARIN regularly receives AS numbers back into our inventory either
through returns or revocation due to non-payment of registration fees in
accordance with the ARIN Registration Services Agreement. When we
receive these returns or make these revocations, we hold the subject AS
numbers outside of the active inventory for a period of time to help
prevent potential disputes for new registrants who might receive these
recycled AS numbers. At certain times of the year, ARIN registration
staff conducts a review of these held AS numbers for re-introduction
into our active inventory. When that happens, recycled AS numbers from
the 2-byte range are sometimes included in the batch that gets added to
our active inventory.

We still occasionally receive a request from a new AS number registrant
who received a 4-byte AS number during the request process to have that
exchanged for a 2-byte AS number. We accommodate those requests when
they are made and conduct a review of our inactive (held) inventory to
identify a suitable 2-byte AS number for the customer. Over the last two
years, requests to exchange a 2-byte for a 4-byte AS number have
decreased in frequency. In the last year, we averaged fewer than two
requests of this type per month.

At the time of writing this ACSP response, ARIN's AS number inventory
consisted of:

Active Inventory (ready to be issued)
2-byte: 303
4-byte: 677

Inactive Inventory (held returns or revocations)
2-byte: 1,019
4-byte: 44

Over time, the AS numbers from our inactive inventory will continue to
be added to our active inventory. At the same time, however, we will
continue to reclaim AS numbers through voluntary customer returns and
ARIN revocations due to non-payment of registration fees.

Going forward, ARIN staff will provide a bi-annual report on the status
of both our active and inactive AS number inventories, including data
separation for 2-byte and 4-byte ranges. This information will be
featured in the Registration Services Department report presented at the
ARIN meetings in April and October of each year and published along with
the associated meeting reports on the ARIN website.

Thank you for participating in the ARIN Consultation and Suggestion
Process. We are closing your suggestion with the commitment to continue
providing this information on a bi-annual basis going forward.


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

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