- Construction and Standards:
- X.509 Standard: Digital certificates contain specific identifying information and are constructed according to the international X.509 standard. This standard defines the format of public key certificates and the process for their creation and validation.
- Signing of Certificates:
- Who Signs: A digital certificate is signed by a trusted third party (usually a Certificate Authority) who vouches for the identity of the certificate holder, rather than by the certificate holder themselves.
- Certificate Revocation Lists (CRLs):
- Purpose: CRLs are lists maintained by Certificate Authorities that contain the serial numbers of digital certificates that have been revoked before their expiration dates.
- Contents: CRLs include the serial numbers of the revoked certificates, along with the date and time when the revocation took effect.
- Usage: Used to verify whether a certificate is still valid or has been revoked, ensuring that compromised certificates are no longer trusted.
These components are crucial for managing trust and security in digital communications, ensuring that digital certificates remain reliable tools for authentication and encryption.