X.509 Certificates (RFC 5280)

1. Overview and certification path

   Certificates, CAs, trust anchors and path building.

2. Basic certificate fields

   Version, serialNumber, issuer, validity, subject and SubjectPublicKeyInfo.

3. Validity

   notBefore and notAfter semantics.

4. Certificate extensions

   Critical and non-critical extensions.

5. Key usage

   keyCertSign, digitalSignature, keyEncipherment and others.

6. Subject alternative name

   DNS names, IPs and emails identifying the subject.

7. Basic constraints

   CA flag and path length constraints.

8. Certificate revocation lists

   CRL profile and extensions.

9. Certification path validation

   Basic path validation algorithm.

10. Online Certificate Status Protocol

    OCSP request and response.

11. Service identity verification

    Matching reference identifiers against certificate names.

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