Which of the following statements best describes a certification authority?
A.
A certification authority is a technique to authenticate digital documents by using computer
cryptography.
B.
A certification authority is a type of encryption that uses a public key and a private key pair for
data encryption.
C.
A certification authority is an entity that issues digital certificates for use by other parties.
D.
A certification authority is a type of encryption that uses a single key to encrypt and decrypt
data.
Explanation:
A certification authority (CA) or certificate authority is an entity that issues digital
certificates for use by other parties. It is an example of a
trusted third party. A CA issues digital certificates that contain a public key and the identity of the
owner. The matching private key is not
similarly made available publicly, but kept secret by the end user who generated the key pair. The
certificate is also an attestation by the CA
that the public key contained in the certificate belongs to the person, organization, server or other
entity noted in the certificate. A CA’s
obligation in such schemes is to verify an applicant’s credentials, so that users and relying parties can
trust the information in the CA’s
certificates. A variety of standards and tests are used by CAs to do so.
If the user trusts the CA and can verify the CA’s signature, then he can also verify that a certain
public key does indeed belong to a person
identified in the certificate.
Answer options B and D are incorrect. A certification authority (CA) is not a type of encryption.
Answer option A is incorrect. A certification authority (CA) does not authenticate digital documents
by using computer cryptography. In order
to authenticate digital documents by using computer cryptography, a digital signature should be
used.