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Guidelines for Requesting an
AS Number

This is an overview of the step-by-step processes by which an organization can request the assignment of an Autonomous System Number (ASN), and how to manage the record of that assignment.

An ASN is a globally unique number that is used to identify an Autonomous System (AS) and it enables an AS to exchange exterior routing information with neighboring AS numbers. An AS is a connected group of IP networks that adhere to a single and clearly defined routing policy. Sites that do not require a unique AS Number should use one or more of the AS Numbers reserved for private use. Those numbers are 64512 through 65535.

Obtaining an AS Number

Step 1 - Requirements

First, an organization should review ARIN's AS policies to determine if it meets the requirements to receive an ASN. The action of requesting resources from ARIN indicates you have read and agree to abide by these policies.

Each organization that is allocated number resources from ARIN must first have established Points-of-Contact (POC) handles and an Organization Identifier (Org ID) with ARIN. Additional information about creating and managing POCs and Org IDs is available in ARIN's Guidelines for Managing Organization and Contact Identifiers.

Once an organization has POCs and an Org ID registered in the ARIN database, it may complete and submit the AS Number Request template. All AS number requests must be sent from the Admin or Tech Point of Contact (POC) associated with the organization's Org ID.

Step 2 - Completing the Template

ARIN assigns both 2-byte (16-bit) and 4-byte (32-bit) AS numbers. Formerly, AS numbers were always 2-bytes, starting at AS1 and ending at AS65535. The introduction of 4-byte AS numbers extends the assignable range from AS65536 through AS4294967295.

The first question on the template asks you whether you would like to request a 4-byte AS number. If so, indicate "YES". When indicating "YES", please ensure your routing equipment and any transit providers or peers are ready and able to accept 4-byte AS numbers when exchanging routing information via BGP.

If you are unsure whether to request a 2-byte or 4-byte AS number, ARIN advises you to indicate "NO" in field 04. Doing so will result in the assignment of the traditional 2-byte AS number.

When completing the template, the organization must first establish the justification for the request. Justification can be made by meeting at least one of the following two requirements.

Multi-homed:

If an organization is multi-homed, or if it will be multi-homed within the next thirty (30) days, it must show exactly how it is connected to the Internet by providing the following information:

  1. Exterior gateway protocol to be used
  2. The IP network addresses that will make up the Autonomous System
  3. Technical point of contact information for each of its upstream providers/peers (full name and e-mail address for verification)

Unique Routing Policy:

An organization must explain how its routing policy is different from its provider's.

When completing the template, note that instructions on what information is required for each line is provided at the bottom of the document. In order to ensure prompt and accurate processing of your AS Number Request Template, please be sure to follow these instructions exactly. Any errors found may result in the template being returned for correction.

Step 3 - Submittal of Template and Auto Response

Upon successfully submitting the template, ARIN verifies its receipt of the request and issues a ticket number via e-mail to the individual who submitted the request. Based on the volume of requests, this may take up to 60 minutes.

Step 4 - Review Process

ARIN reviews and responds to a request within three (3) business days.

The response may include a request for additional information. For each question and response cycle, ARIN responds within three (3) business days. If ARIN does not receive a response within sixty (60) days, the ticket is considered closed and the request must be resubmitted. A response from ARIN requesting additional documentation or information does not imply a request will be denied; it simply means that additional information is needed to evaluate the request.

For questions about requests, communicate via e-mail to hostmaster@arin.net or call ARIN's Registration Services Help Desk at +1.703.227.0660. When contacting the Help Desk, have appropriate ticket numbers and other request documentation readily available, and have access to the ARIN website. In follow-up communication, supply the name of the ARIN Help Desk Resource Analyst that provided previous assistance. Click here for additional guidance on calling the Help Desk.

Step 5 - Request Approval

ARIN notifies your organization, via e-mail to the individual who submitted the request, whether the request was approved or not. The approval is good for sixty (60) days. If your organization does not follow up on the approval within that time, you must resubmit the request.

If your request is rejected and you feel that it has the proper justification for receiving the requested resource, you may contact ARIN to further explain its position.

Step 6- Fee Payment and Registration Services Agreement

As outlined in ARIN's Fee Schedule, a one-time registration fee of $500 (US) is charged for each ASN assigned. After an organization receives confirmation of approval from ARIN and has a ticket number, it must submit a completed AS Billing Account Form. Additional fee and payment information is available in the Billing section.

ARIN does not accept purchase orders as the equivalent of payment and payment information is not accepted by phone. The approval of a request can be dependent on the billing status of the Org ID in question. Outstanding fees due to ARIN must be paid before additional resources are allocated.

Submission of Signed Registration Services Agreement (RSA)

All applicants requesting resources from ARIN are required to sign the Registration Services Agreement (RSA). The RSA must be signed and returned before ARIN allocates resources. The RSA cannot be altered or modified. If the organization already has a signed RSA on file with ARIN, a new one is not needed unless the request for resources will be issued under a new Org ID. Organizations may fax a signed, but otherwise unaltered, RSA to +1.703.227.0671. ARIN requests that the organization also forward two (2) signed originals via postal mail to:

ARIN
Attention: Financial Services Department
3635 Concorde Parkway, Suite 200
Chantilly, VA 20151

Submission of Payment

When completing ARIN's online billing forms, organizations may choose between two payment options:

Immediate online payment by credit card (American Express, Discover, MasterCard, and Visa)

If payment is by credit card, an automatic receipt is e-mailed to the organization, along with instructions on how to download the Registration Services Agreement (RSA).

Receive an invoice for payment by check or wire transfer

For organizations choosing to receive an invoice, ARIN sends an invoice within three (3) business days and instruction on how to download the Registration Services Agreement (RSA). For instructions to send payment by wire transfer, call +1.703.227.9886 or e-mail billing@arin.net.  For wire instructions by e-mail, include the ARIN ticket or invoice number, the organization name, and Org ID. For payments by check, send payment to:

ARIN
Attention: Financial Services Department
3635 Concorde Parkway, Suite 200
Chantilly, VA 20151

Step 7- Assignment of AS Number

The ASN will be assigned within two (2) business days of ARIN's receipt of the organization's registration fee and a signed Registration Services Agreement (RSA). The assignment of an ASN does not qualify organizations for ARIN membership. Only organizations that receive and pay for a direct allocation of IP address space from ARIN are automatically accorded membership.

As membership is open to all interested parties, any organization or individual may also become a member of ARIN through the completion of a Membership Application Form and payment of an annual membership fee of $500 (US).

Managing an AS Number Assignment Record

Organization and Contact Identifiers

To ensure the efficient and accurate processing of all requests related to its allocation, an organization should promptly update its organization's Org ID and POC records after any change. Additional information about Org IDs and POCs is available in ARIN's Guidelines for Managing Organization and Contact Identifiers.

Maintenance Fee and Exemptions

ARIN assesses a single consolidated annual maintenance fee to each Org ID for certain resources registered with it. This single fee covers all ASNs, end-user assignments, and transfers registered with ARIN per Org ID. This fee is due on the anniversary date of the organization's first resource registration associated with their Org ID.

ISPs that are current ARIN subscription holders will not be charged the annual maintenance fee.

Additional information about ARIN's fees is available on the Fee Schedule and the Guidelines for Billing Procedures pages.

Modifying or Returning an AS Number Assignment

There are two types of changes that can be made to an AS number assignment record.

Modification

The AS Number Modification (ASN-Mod) template can be used to change the POC handle associated with an AS number or to modify an AS name. Modifications are submitted by the Administrative or Technical POC for the appropriate Org ID, or the Technical POC for the resource.

If you wish to change POCs associated with an AS number assignment record, the POCs must already exist. If the POCs are not currently registered in the ARIN database, submit a POC template prior to submitting the ASN-Mod template.

Return

The AS Number Modification template can also be used to return unused AS numbers to ARIN. Returns of an AS number can only be submitted by the Administrative POC.

Transfers of AS Numbers

Transfers of ASNs are handled in a similar manner to the transfer of any ARIN resource. Specific guidelines for this process are provided in ARIN's Guidelines for Transferring Internet Number Resources document.