Use Internet2 SiteID

Already have an Internet2 SiteID?
Sign in here.

Internet2 SiteID

MACE Registries


The OID and URN registries lend structural support to trust, identity and middleware applications by providing common definitions, assignment mechanisms and consistent guidelines and implementation practices.

Object Identifier (OID) Registry

The Object Identifier (OID) arc, supports the assignment of unique, global, persistent oids to resources of various kinds for Internet2/Trust and Identity projects and working groups.

Uniform Resource Name (URN) Registry

The URN namespace supports the assignment of unique, global, persistent names to resources of various kinds. The Namespace Identifier (NID) of the namespace is "urn:mace".

NOTE: As of 2015, Internet2 encourages the use of URLs in preference to URNs. See FAQ for more information.

For more details, visit the Features and Registries tabs.


View current registries in the Registries tab.

OID Registry

OIDs are used to identify protocol and schema objects in several different technical areas, including X.500/LDAP-based directories, and X.509-based public-key infrastructure.

Internet2 does not delegate OID registration to other organizations. One OID registry that does do this is IANA,

URN Registry

Internet2 administers a Uniform Resource Name (URN) namespace, supporting the assignment of unique, global, persistent names to resources of various kinds by MACE and its delegates. The Namespace Identifier (NID) of the namespace is "urn:mace".

NOTE: As of 2015, Internet2 encourages the use of URLs in preference to URNs. See here for more information.

The Informational RFC, RFC 3613, Defines the "urn:mace" namespace and describes the procedures and policies governing its use.

Other URN-related information includes:

  • RFC 3406, "Uniform Resource Names (URN) Namespace Definition Mechanisms", describes how URN namespaces are registered.

  • RFC 2141, "URN Syntax", defines the syntax of URNs.

  • The IANA URN Namespace Registry page lists all currently registered URN Namespaces.
These registries are provided as a service to the community. There is no charge associated with using them.
Is it recommended to use URLs or URNs?

For most purposes, URLs are at least as good as URNs and may even be preferred in many situations. In particular, if your goal is to craft globally unique values for eduPersonEntitlement or similar purposes, you should consider using URLs based on a registered domain you control.

What are the benefits of using URLs instead of URNs?

Benefits of using URLs instead of URNs include:

- Legitimate URL values are globally unique if a suitable domain is used and a delegation model is in place for defining paths under that root domain. For example, if you own domain and wish to craft URL values for eduPersonEntitlement, register a subdomain with your HTTP domain authority. One choice might be No one else has the legal right to craft values under that subdomain, so assignments you make under that subdomain will be globally unique as long as they are locally unique.

-If the URLs actually resolve to web pages, it is possible to make the assigned values self-documenting by posting a definition of the value at that URL.

OID Registry

Click here for a current list of registered OIDs

To request an OID, send an email to

URN Registry

Click here for a current list of registered URNs

Use this form to request a urn:mace namespace.

NOTE: As of 2015, Internet2 encourages the use of URLs in preference to URNs. See here for more information.


Information for organizations requesting a delegated namespace

Some urn:mace namespaces are administered by Internet2, on behalf of Internet2 and Trust and Identity related projects and services, while other namespaces are delegated to other organizations, to be administered by them. Representatives of organizations interested in registering a urn:mace namespace should first read RFC 3613, and consider the following:

  • The URN registry supports the mission of promoting standardization and interoperability in middleware for research and education networking. Internet2 is pleased to consider requests consistent with that mission, and reserves the right to deny inappropriate requests.

  • Stability is a key element of URN-based naming. Organizations operating urn:mace delegated namespaces agree to notify <mace-submit AT> with any changes, including changes in contact persons, etc.

  • The primary contact should be in a decision-making role for the organization and authorized to act on behalf of the organization in this capacity. The primary contact must be involved in the communication with Internet2 regarding the registration.
  • URNs are delegated to the following classes of registrants:
    1. Universities and colleges, preferably with a request to register the top-level institutional domain, e.g. in the US, to register
    2. Corporations providing services to higher education and research, again preferably to the top-level domain for the corporation
    3. Federations, Projects, Consortia, Institutes and Projects in the higher education and research space given the following conditions:
      • The organization has a registered domain name, and the registration request is for that domain name.
      • The organization is intended to be in existence for several years at minimum
      • The primary registrant is a principal within the relevant organization and is also concurrently in the employ of a university, college or other institution of higher education

      Non-institutional activities seeking URNs should try to get them via a delegation from one of their supporting institutions, rather than directly from Internet2.
  • Discoverability is another important element of URN-based naming. Organizations are strongly encouraged to maintain accurate information describing names they have registered in their delegated namespace.
  • Subspaces of delegated namespaces may be further delegated to other organizations. urn:mace delegates are encouraged to follow the same principles and procedures in managing its delegations.