CA Certificates Technical Reference
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2
Certification authority (CA) certificates are certificates issued by a CA to itself or to a second CA for the purpose of creating a defined relationship between the two CAs. A certificate that is issued by a CA to itself is referred to as a trusted root certificate because it is intended to establish a point of ultimate trust for a CA hierarchy. Once the trusted root has been established, it can be used to authorize subordinate CAs to issue certificates on its behalf. Although the relationship between CAs is most commonly hierarchical, CA certificates can also be used to establish trust relationships between CAs in two different public key infrastructure (PKI) hierarchies. In all of these cases, the CA certificate is critical to defining the certificate path and usage restrictions for all end entity certificates issued for use in the PKI.
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