What should you recommend?

Your network contains a standalone root certification authority (CA). You have a server named Server1 that runs Windows Server 2008 R2. You issue a server certificate to Server1. You deploy Secure Socket Tunneling Protocol (SSTP) on Server1.

You need to recommend a solution that allows external partner computers to access internal network resources by using SSTP.

What should you recommend?

Your network contains a standalone root certification authority (CA). You have a server named Server1 that runs Windows Server 2008 R2. You issue a server certificate to Server1. You deploy Secure Socket Tunneling Protocol (SSTP) on Server1.

You need to recommend a solution that allows external partner computers to access internal network resources by using SSTP.

What should you recommend?

A.
Enable Network Access Protection (NAP) on the network.

B.
Deploy the Root CA certificate to the external computers.

C.
Implement the Remote Desktop Connection Broker role service.

D.
Configure the firewall to allow inbound traffic on TCP Port 1723.

Explanation:
Lesson 1: Configuring Active Directory Certificate Services

Certificate Authorities are becoming as integral to an organizations network infrastructure as domain controllers, DNS, and DHCP servers. You should spend at least as much time planning the deployment of Certificate Services in your organizations Active Directory environment as you spend planning the deployment of these other infrastructure servers. In this lesson, you will learn how certificate templates impact the issuance of digital certificates, how to configure certificates to be automatically assigned to users, and how to configure supporting technologies such as Online Responders and credential roaming. Learning how to use these technologies will smooth the integration of certificates into your organizations Windows Server 2008 environment.

After this lesson, you will be able to:
Install and manage Active Directory Certificate Services.
Configure autoenrollment for certificates.
Configure credential roaming.
Configure an Online Responder for Certificate Services.

Estimated lesson time: 40 minutes

Types of Certificate Authority
When planning the deployment of Certificate Services in your network environment, you must decide which type of Certificate Authority best meets your organizational requirements. There are four types of Certificate Authority (CA):
Enterprise Root
Enterprise Subordinate
Standalone Root
Standalone Subordinate

The type of CA you deploy depends on how certificates will be used in your environment and the state of the existing environment. You have to choose between an Enterprise or a Standalone CA during the installation of the Certificate Services role, as shown in Figure 10-1. You cannot switch between any of the CA types after the CA has been deployed.

Figure 10-1Selecting an Enterprise or Standalone CA

Enterprise CAs require access to Active Directory. This type of CA uses Group Policy to propagate the certificate trust lists to users and computers throughout the domain and publish certificate revocation lists to Active Directory. Enterprise CAs issue certificates from certificate templates, which allow the following functionality:
Enterprise CAs enforce credential checks on users during the certificate enrollment process. Each certificate template has a set of security permissions that determine whether a particular user is authorized to receive certificates generated from that template.
Certificate names are automatically generated from information stored within Active Directory. The method by which this is done is determined by certificate template configuration.
Autoenrollment can be used to issue certificates from Enterprise CAs, vastly simplifying the certificate distribution process. Autoenrollment is configured through applying certificate template permissions.

In essence, Enterprise CAs are fully integrated into a Windows Server 2008 environment. This type of CA makes the issuing and management of certificates for Active Directory clients as simple as possible.
Standalone CAs do not require Active Directory. When certificate requests are submitted to Standalone CAs, the requestor must provide all relevant identifying information and manually specify the type of certificate needed. This process occurs automatically with an Enterprise CA. By default, Standalone CA requests require administrator approval. Administrator intervention is necessary because there is no automated method of verifying a requestors credentials. Standalone CAs do not use certificate templates, limiting the ability for administrators to customize certificates for specific organizational needs.

You can deploy Standalone CAs on computers that are members of the domain. When installed by a user that is a member of the Domain Admins group, or one who has been delegated similar rights, the Standalone CAs information will be added to the Trusted Root Certificate Authorities certificate store for all users and computers in the domain. The CA will also be able to publish its certificate revocation list to Active Directory.
Whether you install a Root or Subordinate CA depends on whether there is an existing certificate infrastructure. Root CAs are the most trusted type of CA in an organizations public key infrastructure (PKI) hierarchy. Root CAs sit at the top of the hierarchy as the ultimate point of trust and hence must be as secure as possible. In many environments, a Root CA is only used to issue signing certificates to Subordinate CAs. When not used for this purpose, Root CAs are kept offline in secure environments as a method of reducing the chance that they might be compromised.

If a Root CA is compromised, all certificates within an organizations PKI infrastructure should be considered compromised. Digital certificates are ultimately statements of trust. If you cannot trust the ultimate authority from which that trust is derived, it follows that you should not trust any of the certificates downstream from that ultimate authority.

Subordinate CAs are the network infrastructure servers that you should deploy to issue the everyday certificates needed by computers, users, and services. An organization can have many Subordinate CAs, each of which is issued a signing certificate by the Root CA. In the event that one Subordinate CA is compromised, trust of that CA can be revoked from the Root CA. Only the certificates that were issued by that CA will be considered untrustworthy. You can replace the compromised Subordinate CA without having to replace the entire organizations certificate infrastructure. Subordinate CAs can be replaced, but a compromised Enterprise Root CA usually means you have to redeploy the Active Directory forest from scratch. If a Standalone Root CA is compromised, it also necessitates the replacement of an organizations PKI infrastructure.



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