MI Namespace

Last updated: January 30, 2023
Audience: IT Staff / Technical

This is the official naming document for the Microsoft Infrastructure service


This document describes the syntax of identifiers in Microsoft Infrastructure (MI).  It is updated as needed as MI is extended to support new functionality.

Principles and Constraints

MI not only publishes objects from other services, such as the groups service and the UW NetID service, but it also acts as the authority for other objects, such as exchange resources, contacts, and computers.  This service is constrained by the UW NetID Namespace and the Groups Namespace.

Objects have multiple naming attributes: samAccountName, CN (or OU), displayName, and sometimes others (e.g. alias). For the purposes of this document, samAccountName and CN (or OU) are the naming attributes in scope and should be set to a matching value. We do not constrain displayName or other naming attributes.

Some common constraints and items worth calling out:

  • Active Directory user objects, groups, contact objects and resource objects all share the same namespace and therefore are constrained by UW NetID and Group naming
  • Group Policy and Computer objects are not constrained by the UW NetID and Group naming
  • MI connectors that manage users and groups generally set CN and samAccountName to the same value and reflect the constraints of the least flexible of the two attributes



No restrictions in common across all object types

MI User Objects

MI Contact Objects

  • 6-13 octets
  • Lower case ASCII letters, digits and underscores
  • Must be of the form:  c_ followed by the email address with the @ replaced by an underscore

MI Computer Objects

NOTE: This also applies to Group Managed Service Account (gMSA) Objects.

MI Group Objects

NOTE: MI-only groups are possible (but discouraged) which do not follow the Groups Namespace. These generally are only allowed:

  • when a vendor product must use a name that does not conform, or
  • there is some reason for the group to not be managed via the Groups Service

For the latter case, MI-only groups should have a prefix of g_.

MI Group Policy

NOTE: This also applies to IPsec Objects.

MI Resource Objects

  • Prefixed by r_
  • Must meet user object constraints noted above

Note: Resource objects must meet requirements of MSCA service. They currently are only created by the MSCA service and are not present in the UW NetID system and derivative systems.

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