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Manage Resources

API Keys

An Application Programming Interface (API) Key is a shared secret that can be used to identify yourself in your interactions with ARIN. Whether submitting email templates or calls into ARIN’s RESTful Provisioning system, you will need an API key. Learn how to create, manage and use your API keys to authenticate your transactions.

Report Reassignments and Reallocations

Organizations that receive IPv4 or IPv6 address space allocations from ARIN directly or as a downstream customer of another organization must provide reassignment/reallocation information via either Referral Whois (RWhois), the Shared Whois Project (SWIP), or a distributed service in compliance with ARIN policy.

Resource Modifications

A Network Modification request is used to change the network name, origin AS, POC handle(s), and public comments on an IP address block.  Please note that changes to reverse DNS delegation cannot be made with a network modification. 

ASN Modifications can be done using the ASN request form available in ARIN Online.

Returning Resources

ARIN welcomes the return of any unused or unneeded resources so they may be added back to our pool of available Internet number resources for issuance to other organizations.

To learn more about returning your resources, visit the Understanding the Return and Revocation Process page.

Reverse DNS

Reverse DNS is used to determine the domain name that is associated with a given IP address using the Domain Name System (DNS). The process of acquiring reverse resolution is accomplished using PTR records that are rooted in the domain. ARIN requires organizations to maintain their domain records. The ARIN Online delegation management tools and ARIN's RESTful Provisioning system enable you to individually manage nameservers and to register Delegation Signer (DS) Resource Records for DNSSEC for each reverse delegation within both IPv4 and IPv6 networks.

Internet Routing Registry (IRR)

ARIN's Internet Routing Registry (IRR) service allows network operators to submit, maintain, and retrieve router configuration information abstracted from the languages and syntaxes utilized by router configuration software. The Routing Registry page offers a detailed explanation of how to access and utilize this information to support your organization.

Resource Public Key Infrastructure (RPKI)

ARIN Online users may now participate in RPKI: an opt-in service that allows users to certify their Internet number resources to help secure Internet routing. This initiative has been developed within the IETF's SIDR Working Group, with involvement from Regional Internet Registries (RIRs), and numerous Internet Service Providers (ISPs).

ARIN encourages members of the Internet community to certify their resources through RPKI. Internet routing today is vulnerable to hijacking and the provisioning/use of certificates is one of  first steps required to make routing more secure. Widespread RPKI adoption will help simplify IP address holder verification and routing decision-making throughout the ARIN region.

For more information about this crucial step in securing Internet routing, visit ARIN’s RPKI Home Page.

Legacy Number Resources

The Legacy Registration Services Agreement (Legacy RSA or LRSA) has been offered to those organizations and individuals in the ARIN service region who hold legacy Internet number resources not covered by any other Registration Services Agreement (RSA) with ARIN. Legacy holders who sign up have been guaranteed the same services provided to other organizations who have a signed RSA with ARIN. Legacy holders will still enjoy this benefit; however, this will be now done by executing a new RSA document that combines the Legacy RSA and the RSA into a single document. This combined RSA document is also now being offered to non-legacy holders.

There is an annual maintenance fee for Legacy holders who sign the combined RSA. The annual invoice will be sent to the designated billing Point of Contact (POC) approximately 60 days before it is due.

If you have questions, please see the "Legacy RSA" section of the Registration Services Agreement FAQ or the Legacy Number Resource Information page.

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