What attribute is included in a X.509-certificate?

A.
Distinguished name of the subject

B.
Telephone number of the department

C.
secret key of the issuing CA

D.
the key pair of the certificate holder

Explanation:
An X.509 certificate contains information about the identity to which a certificate is issued and the identity that
issued it. Standard information in an X.509 certificate includes:
Version – which X.509 version applies to the certificate (which indicates what data the certificate must
include)
Serial number – the identity creating the certificate must assign it a serial number that distinguishes it from
other certificates
Algorithm information – the algorithm used by the issuer to sign the certificate
Issuer distinguished name – the name of the entity issuing the certificate
Validity period of the certificate – start/end date and time
Subject distinguished name – the name of the identity the certificate is issued to
Subject public key information – the public key associated with the identity
Extensions (optional)
Incorrect Answers:
B: The telephone number of the department is not included in an X509 certificate.
C: The secret key of the issuing CA is not included in an X509 certificate. The secret key is the private key
which is never distributed.
D: The key pair of the certificate holder is not included in an X509 certificate. A key pair includes a private key
which is kept private.

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