PullManagement is performed by using the CertificateManager information model, in particular the Methods defined in 7.9. The interactions between Application and CertificateManager during PullManagement are illustrated in Figure 14.

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Figure 14 – The Pull Management Model for Certificates

The Application Administration component may be part of the Client or Server or a standalone utility that understands how the application persists its configuration information in its Configuration Database.

A similar process is used to renew certificates or to periodically update Trust List.

Security in PullManagement requires an encrypted channel and authorized credentials. These credentials may be user credentials for a CertificateAuthorityAdmin or application credentials determined by the Certificate used to create the SecureChannel. Examples of the application credentials include Certificates previously issued to the application being accessed, Device Certificates issued by the Registrar defined in OPC 10000-21 or Certificates isssued to an application with accesss to the ApplicationAdmin Privilege (see 6.2).