Gartner Research

Decision Point for Directory Categories, Instances and Roles

Published: 09 July 2012

ID: G00235109

Analyst(s): Kevin Kampman , Ian Glazer


This Decision Point defines concepts such as directory categories, directory instances and directory roles. It also provides the criteria that enterprises should use to determine which types of directory services to deploy, and when to consolidate or separate directory instances.

Table Of Contents

Decision Point

Decision Context

  • Related Decisions

Evaluation Criteria

  • Requirements and Constraints
  • Splitting Categories
    • Physical Requirements
    • Structural Requirements
    • Organizational/Security Requirements


  • Special-Purpose Directories
  • Enterprise Directories
  • Externally Facing Directories

Future Developments

  • Convergence of Special-Purpose and Enterprise Directory Environments
  • Convergence of Externally Facing and Enterprise Directories
  • Role of Directories in Identity Services Layer
  • Consolidation of Special-Purpose Directories
  • Directory Services in the Cloud

Decision Tool

  • Directory Category Decision
    • Subsidiary Decision 1: Deploy the Directory for an Application-Specific Category or Role
    • Subsidiary Decision 3: Deploy the Directory for an Enterprise Category or Role
    • Subsidiary Decision 5: Deploy the Directory for an Externally Facing Category or Role
  • Directory Instance Decision
    • Separating and Combining Directory Instances Across Categories Decision
    • Subsidiary Decision 7: The Externally Facing Directory Instances Should Always Be Separate From the Special-Purpose/NOS Directory Instances
    • Subsidiary Decision 9: Consolidate the NOS Directory Instances With Enterprise Directory Instances Where Feasible
    • Do Not Combine the NOS Directory Instances and Enterprise Directory Instances
    • Subsidiary Decision 11: Deploy a Separate Externally Facing Directory Instance, and Possibly One Externally Facing Directory Instance per Customer
    • Combine the Externally Facing and Enterprise Directory Instances Where Feasible
    • Deploy Separate Multipurpose Directory Instances for Each Directory Category and Role
    • Creating Additional Directory Instances Within a Category Decision
    • Restructure Existing or Create Additional Directory Instances Within the Category
    • No Additional Directory Instances Should Be Deployed Within the Category

©2021 Gartner, Inc. and/or its affiliates. All rights reserved. Gartner is a registered trademark of Gartner, Inc. and its affiliates. This publication may not be reproduced or distributed in any form without Gartner’s prior written permission. It consists of the opinions of Gartner’s research organization, which should not be construed as statements of fact. While the information contained in this publication has been obtained from sources believed to be reliable, Gartner disclaims all warranties as to the accuracy, completeness or adequacy of such information. Although Gartner research may address legal and financial issues, Gartner does not provide legal or investment advice and its research should not be construed or used as such. Your access and use of this publication are governed by Gartner’s Usage Policy. Gartner prides itself on its reputation for independence and objectivity. Its research is produced independently by its research organization without input or influence from any third party. For further information, see Guiding Principles on Independence and Objectivity.

Already have a Gartner Account?

Become a client

Learn how to access this content as a Gartner client.