Online Responders in Windows Server 2008 R2 and Windows Server 2008 use the Microsoft certificate revocation list (CRL)-based revocation provider to provide certificate status. This revocation provider is the component that an Online Responder contacts to check the status of a certificate. The revocation provider is responsible for obtaining updated CRLs and determining the status of a certificate based on this CRL.

You can select one or more CRLs and delta CRLs for use with the Online Responders in your Array, and you can define how often the provider receives updated CRLs.