The Regional Internet Registry Structure


February, 2006 By the Number Resource Organization (NRO)

This document is a work product of the Number Resource Organization. It represents the collaborative efforts of the established RIRs (AfriNIC, APNIC, ARIN, LACNIC, and RIPE NCC). Information regarding the Number Resource Organization and the various RIRs is available at the URLs that are listed at the end of this document.

The Regional Internet Registries (RIRs) are responsible, within their assigned regions, for allocating Internet number resources such as globally unique IP addresses (IPv4 and IPv6) and autonomous system numbers. These resources are required by Internet service providers and users to identify elements of the basic Internet infrastructure such as interfaces on routers, switches and computers.

The RIRs were established by Internet service providers during the 1990s, in response to the growth of the Internet and a clear need for improvements in this existing resource management system. They are structured similarly as not-for-profit, open, membership-based organizations, operating as neutral and impartial bodies of industry self-regulation.

RIR Office Location Year established
AfriNIC Ebčne, Mauritius 2005
APNIC Brisbane, Australia 1993
ARIN Chantilly, Virginia, USA 1997 (InterNIC established in 1993)
LACNIC Montevideo, Uruguay 2002
RIPE NCC Amsterdam, The Netherlands 1992

The Regional Internet Registry Policy Development Process

A major function of the RIRs is to facilitate the development of policies needed to guide the management of Internet number resources regionally and globally. This is done in a consensus-based, bottom-up, industry self-regulating manner, in response to the requirements of the many and varied stakeholders in the respective RIR communities. These policy development processes are open to anybody, and often include the active participation of both public and private sector bodies as well as civil society.

Each RIR hosts regular open public policy meetings, which form the primary focal point for policy development in each region. These meetings are open to all interested parties, regardless of membership status, who can participate in discussing IP-related issues and in developing Internet number resource management policies. Formal policy development processes, along with publicly available, open mailing lists, ensure that address management policies take into account broad perspectives on the issues that impact the community. The role of the RIRs is to facilitate these processes and help their communities build consensus-based policies; and then to ensure that these policies are applied fairly and consistently. Further information regarding the various RIR open public policy meetings and how to subscribe to the policy mailing lists is available at the web site of each RIR. The URLs for these web sites is listed at the end of this document. Every reader of this document is invited and encouraged to join the policy discussions by subscribing to the policy mailing lists and, if possible, to attend the policy meetings.

Due to natural regional differences, RIRs may take different approaches in supporting the development and implementation of policies. Regardless of the implementation process used, the RIRs share a common goal: ensuring the fair distribution and responsible stewardship of Internet number resources to best maintain the stability and continued growth of the Internet. The policies of all RIRs are summarized and compared in a document maintained by the Number Resource Organization called the RIR Comparative Policy Overview. This document is available at:

The managerial, administrative, and technical activities of the RIRs form an integral part of the infrastructure needed to keep the Internet operating efficiently.

Regional Internet Registry Co-ordination: The Number Resource Organization

Although existing as separate entities that meet the needs of their respective communities, the RIRs must also work closely together, coordinating activities that support common policies.

In October 2003, the four then existing RIRs - APNIC, ARIN, LACNIC and RIPE NCC - entered into a Memorandum of Understanding (MoU) to form the Number Resource Organization (NRO): Upon AfriNIC''s formal recognition as the fifth RIR, it signed an addendum to the MoU, available online at

The purpose of the NRO is to ensure global coherence of certain RIR activities, and to provide a single common interface to all the RIRs where this is necessary. The NRO also undertakes joint RIR activities, including technical projects and liaison activities. The NRO does not replace or interfere with the regional policy-development processes of the RIRs, nor with any of the RIRs operational activities.

In October 2004, the NRO signed an MoU with the Internet Corporation for Assigned Names and Numbers (ICANN) re-establishing the Address Supporting Organization (ASO). The ASO was originally formed in 1999 by an MoU between the RIRs and ICANN, and has been reformed as a consequence of the ICANN reform processes. The purpose of the ASO is to review and develop recommendations on Internet number resource policy and to advise the ICANN Board on these matters. The new ASO MoU stipulates how the NRO will fulfill the role, responsibilities and functions of the ASO as outlined in the ICANN Bylaws:

This article is also available in PDF and ASCII.

Expanded Coverage from ISOC

In-depth articles, papers, links and other resources on a variety of topics are available from the ISOC site at:


The RIR framework provides an open, transparent and documented process for developing Internet number resource policy that is in step with the needs of the RIR communities. It contributes to their common goal and purpose of ensuring fair distribution, responsible management and effective utilization of number resources necessary to maintain the stability of the Internet.

ISOC Position

The RIRs have a long history of successful operation. They follow fair and open principles and practices in the administration of Internet address space, the Internet's most important technical resource. ISOC strongly supports the RIRs independence from commercial and governmental interests.

For More Information

More information on the development of the Regional Internet Registry system is available at Cisco's website.


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