You are about to install Certificate Services for the first time on your Windows 2000 network. You will install Certificate Services on a Windows 2000 Server computer that is a member of the domain, and you want the certification authority (CA) to integrate with and use Active Directory for publishing certificates and certificate revocation lists. Which type of CA should you select when you install Certificate Services?

Introduction / Context:
Windows 2000 Certificate Services can create different types of certification authorities (CAs), such as Enterprise and Stand alone, root and subordinate. The type you choose affects how the CA integrates with Active Directory, how certificate templates are used and how trust is established. When deploying a public key infrastructure in an Active Directory environment, the first CA installed often plays a special role as the root of trust for the organization.

Given Data / Assumptions:

• You are installing Certificate Services for the first time in the Windows 2000 environment.
• The server is a member of an Active Directory domain.
• You want the CA to use Active Directory to publish certificates and certificate revocation lists.
• No other CAs currently exist in the organization.

Concept / Approach:
Enterprise CAs integrate with Active Directory, automatically publishing certificates and using certificate templates stored in the directory. Stand alone CAs do not integrate with Active Directory in the same way and usually require more manual management of certificate requests and publication. A root CA is at the top of the CA hierarchy for that organization, while a subordinate CA chains to a higher level CA. Because this is the first CA and you want Active Directory integration, an Enterprise root CA is the appropriate choice.

Step-by-Step Solution:
Step 1: Recognise that you want Active Directory integration, so you must choose an Enterprise CA rather than a Stand alone CA.Step 2: Determine whether this CA will be the top of the hierarchy. Because this is the first CA in the environment, it will act as the root for the organization.Step 3: Understand that a Stand alone root CA would not integrate fully with Active Directory, which conflicts with the requirement.Step 4: Recognise that Enterprise subordinate CAs require an existing root CA to chain to, which you do not yet have.Step 5: Exclude Stand alone subordinate CA for the same reason and because it does not provide directory integration.Step 6: Conclude that an Enterprise root CA is the correct type for this first deployment.

Verification / Alternative check:
Microsoft documentation on Windows 2000 Certificate Services states that Enterprise CAs rely on Active Directory and make use of certificate templates for automatic issuance and enrollment. For organisations with Active Directory, Enterprise CAs provide a more automated and integrated solution than Stand alone CAs. The first CA in such an environment is typically an Enterprise root CA, establishing the root of trust for subsequent Enterprise subordinate CAs if needed.

Why Other Options Are Wrong:
An Enterprise subordinate CA would integrate with Active Directory but assumes the existence of a parent CA already in place. A Stand alone root CA can serve as a root but does not take advantage of Active Directory features like certificate templates and automatic publishing. A Stand alone subordinate CA lacks both root authority and directory integration. None of these match the requirement of being the first CA and using Active Directory.

Common Pitfalls:
Some administrators choose a Stand alone CA because they are uncertain about managing Active Directory integration, only to discover later that they miss features like auto enrollment and template based issuance. Others select a subordinate CA type when no root exists, which is not valid. Careful planning of the CA hierarchy and understanding the benefits of Enterprise versus Stand alone types helps avoid difficult migrations later.

Final Answer:
The correct CA type to select in this scenario is Enterprise root CA.