Internet Routing Registry (IRR)

Understanding Internet Routing Registries

Internet Routing Registries (IRRs) contain information — submitted and maintained by ISPs or other entities — about Autonomous System Numbers (ASNs) and routing prefixes. IRRs can be used by ISPs to develop routing plans. For example, ISPs who use Border Gateway Protocol (BGP) can create Access Control Lists to permit or deny traffic in their networks based on route registry information.

The global IRR is comprised of a network of distributed databases maintained by Regional Internet Registries (RIRs) such as ARIN, service providers, and third parties. Some of these databases contain only routing information for a particular region, network, or ISP. Other IRR databases mirror specific IRR databases, and contain IRR information from multiple databases. One of the IRR maintainers provides a list of routing registries.

A world map illustrating connections between the five Regional Internet Registries and other Internet Routing Registries

Overview of the ARIN IRR

The ARIN IRR acts as part of the global IRR, and is a searchable database of routing policy information for networks in the ARIN region. It currently exists in a database that is separate from ARIN’s public Whois.

An illustration of how information flows through Internet Routing Registries

The ARIN IRR stores information in Routing Policy Specification Language (RPSL) objects. These objects can be submitted to the ARIN IRR by ISPs and retrieved by other IRRs when ISPs in their region are requesting ARIN routing information.

How Do I Submit Routing Information?

To create objects in the IRR, you submit templates in plain text email that contain the information you want to add to the database. After submitting objects, you can make changes to them or add more objects by sending additional email templates.

We provide the following resources for you:

  • IRR Quick Start Guide: Helps you set up your maintainer object and create other objects to submit to the IRR.
  • Using the ARIN IRR: Provides information about the ARIN IRR and documents objects, attributes, values, and sample templates.

How Do I Query ARIN’s IRR?

When you’ve created routing registry records, after 24 hours, the most accurate way to view them is to search for them from our public FTP site:

You can also use a command-line interface command in a program such as Terminal to enter query commands such as:

whois -h <object>

Routing data for the object is displayed. In some cases, the ARIN IRR may display objects that it does not have authority over. For these objects, the query results will display placeholder, or “dummy,” data in fields such as the descr:, admin-c:, upd-to:, auth:, and remarks: attributes fields. Additionally, the remarks: attribute field will include the following message: “To view the original object, please query the ARIN Database at:"

Note: You can use Whois queries to view registration information for a specific Organization Identifier (Org ID). However, the Whois and IRR databases are separate and IRR objects are only searchable using, as shown in the previous example.

For a full list of querying instructions, use the following command:

whois -h help

How Do I Submit a Mirroring Request?

ARIN’s IRR mirrors other RPSL databases. To request ARIN mirror your site’s database, please submit an Ask ARIN request using your ARIN Online account and include “MIRRORING REQUEST” in the subject line. You will need to agree to the terms and conditions of the “Routing Registry” section of the ARIN Number Resource Policy Manual (NPRM) and prove that your site’s routing registry data:

  • Is actively maintained
  • Has been updated within the past 30 days
  • Is publicly available
  • Expresses routing policies of use or interest to ARIN’s region

Registration Services Help Desk
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