Installation of a Certificate Enrollment Policy Web Service (CEP)

The following describes how to install the Certificate Enrollment Policy Web Service (CEP).

The Certificate Enrollment Web Services (Certificate Enrollment Policy Web Service, CEP, and Certificate Enrollment Web Service, CES) enable the automatic request and renewal of certificates from a certification authority via a Web-based interface. This eliminates the need to contact the certification authority directly via Remote Procedure Call (RPC). For a more detailed description, see the article "Certificate request basics via Certificate Enrollment Web Services (CEP, CES)„.

The following instructions initially install the roller with the default settings. An adjustment is made in the respective course of the instructions.

Required permissions

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To install the role, it is required that the installing user is a member of the Enterprise Administrators group. Unfortunately, the permission cannot be delegated. For this reason, special care should be taken when using the user account to prevent identity theft.

Authentication methods supported by CEP

The following combinations of authentication methods are possible. These can all be installed together on the same server.

Kerberos authentication
Username/Password Authentication
Username/password authentication with support for key-based renewal
Certificate-based authentication
Certificate-based authentication with support for key-based renewal

Install role files and dependencies

First, the web server role is installed. This step is not strictly necessary, since it is done as a dependency anyway. However, it can be used to ensure that the subsequently required IIS management tools are installed. If there is no Internet Information Service (IIS) Web Server installed on the target server, it can be installed with the default settings and management tools using the following command.

Install-WindowsFeature -Name Web-Server -IncludeManagementTools

Then the binaries for the CEP can be installed.

Install-WindowsFeature -Name ADCS-Enroll-Web-Pol

Request SSL certificate

Since the Certificate Enrollment Web Policy Service works over HTTPS, an SSL certificate is required. How to configure a certificate template for such a certificate is described in the article "Configuring a Secure Socket Layer (SSL) Certificate Template for Web Server" described.

The identity within the SSL certificate must match either the fully qualified server name, or the alias should the CEP be operated with one.

Identify SSL certificate

When installing the CEP role, the SSL certificate just requested must be specified. It can first be identified with the following Powershell command.

Get-ChildItem -Path Cert:\LocalMachine\My

If there are several certificates to choose from, it may help to identify the fingerprint (thumprint) of the certificate via the certificate dialog, for example via the certificate management console for the computer account (certlm.msc).

Subsequently, the identified certificate is stored in a variable (here: $sslcert) cached.

$sslcert = dir Cert:\LocalMachine\My\{thumbprint-of-the-certificate}