Your IP address could not be determined at this time.

Manage and Return 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

As outlined in the ARIN Number Resource Policy Manual (NRPM), organizations that receive IPv4 or IPv6 address space allocations from ARIN directly or as a downstream customer of another organization must provide reassignment information.

Resource Modifications / Returns

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 (IPv4, IPv6, or ASN) directly to ARIN. We will add the returned resources to our available pool of address space. Notify us that you have resources you want to return by either

  • logging into ARIN Online and selecting ASK ARIN,
  • submitting a completed version of one of the two email templates linked to above
  • by emailing and indicating the block(s) you plan to return.

An analyst will contact you to complete the process of returning the resources.

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: a free, 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.

Search Related Content


full site search

Examples: Resource Request Documentation Examples: Resource Request Documentation

Registration Services Help Desk

Interacting With ARIN

Monday through Friday
7:00 AM to 7:00 PM ET
Phone: +1.703.227.0660
Fax: +1.703.997.8844
Tips for Calling the Help Desk