Filling IPv4 Waiting List Requests

Filling IPv4 Waiting List Requests

The line for IPv4 addresses keeps getting longer, but will it ever get shorter? Since ARIN reached full IPv4 depletion on 24 September 2015, organizations with a justified need for IPv4 addresses have the option to be added to ARIN’s IPv4 Waiting List. Currently there are more than 350+ organizations that opted to go that route in the hopes IPv4 address space will come available.

Will any of these organizations ever get space and thus drop off the list?

While it doesn’t happen often or in very big quantities, IPv4 addresses may become available to organizations on the IPv4 Waiting List in several ways:

  • Internet Assigned Numbers Authority (IANA) Redistribution

  • Returned IPv4 Blocks

  • Revoked IPv4 blocks

IANA Redistribution

A global policy allows IANA to redistribute any recovered IPv4 addresses made available to it by the five Regional Internet Registries (RIRs).

This policy requires IANA to give each of the five RIRs an equal share of the total recovered IPv4 address space twice per year.  Previous redistributions and IANA’s current recovered space inventory is posted online.

When IANA redistributes IPv4 space to ARIN, that space is used to fill IPv4 waiting list requests.

Returned IPv4 Blocks

Occasionally organizations will opt to return unused IPv4 blocks to ARIN.  When ARIN receives an IPv4 return request, the organization is informed that return is not required and that transfer options exist.  Should they wish to continue with the return, we will verify the return is authorized by the organization, typically in the form of a notarized letter confirming all aspects of the return.  Upon confirmation, we’ll remove the block from Whois and hold it for a minimum of 60 days in order to conduct the reviews and verifications required to reissue the space. After a final sign off by ARIN’s management and legal team, returned space is made available to fulfill IPv4 waiting list requests.

Revoked IPv4 Blocks

Organizations are required to comply with all terms and conditions of their registration services agreement.  When an organization fails to pay the associated annual registration fee in a timely fashion, their resources could be revoked.  If payment is not made within four months of the due date, the number resources are removed from Whois directory and all registration services (e.g. reverse DNS delegation) cease.  If payment is not made by six months after the due date, the registration revocation is considered permanent and the number resources become available to be reissued (note that there are several other reasons IPv4 blocks may be revoked, e.g. if they were fraudulently obtained, but the most common reason for revocation is because of non-payment.)

Before number resources are reissued, a cross-departmental team review is conducted.  This team of senior Registration Services, Financial Services, and legal staff reviews all available information on the address block, which typically includes:

  • Making sure the block was registered under an RSA/LRSA

  • Researching that all notices of non-payment required by the RSA/LRSA were sent

  • Verifying payment was not made

  • Confirming that a timely re-registration request was not submitted to ARIN (i.e. a request from the previous registrant submitted asking to restore the registration)

  • Confirming the block is not involved in a pending transfer request

  • Checking routing history

  • Checking business registration records

If the team confirms no organization retains a legitimate claim to the registration, the reissuance of the block is confirmed and signed off by ARIN’s management team.  The block is then made available to fulfill IPv4 waiting list requests.

Out of an abundance of caution, returned and revoked IPv4 addresses are not made available to organizations on the waiting list until these processes are completed.

In summary, it is possible for an organization on the waiting list to receive address space, but this is expected to happen rather infrequently after a redistribution, return or revocation occurs.

Post written by:

John Sweeting
Chief Customer Officer, ARIN

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