CISA Certified Information Systems Auditor – Question1621 - CISA Certified Information Systems Auditor

Which of the following would effectively verify the originator of a transaction?

A. Using a secret password between the originator and the receiver
B. Encrypting the transaction with the receiver's public key
C. Using a portable document format (PDF) to encapsulate transaction content
D. Digitally signing the transaction with the source's private key

Correct Answer: D

Explanation:

Explanation:
A digital signature is an electronic identification of a person, created by using a public key algorithm, to verify to a recipient the identity of the source of a transaction and the integrity of its content. Since they are a ‘shared secret’ between the user and the system itself, passwords are considered a weaker means of authentication. Encrypting the transaction with the recipient’s public key will provide confidentiality for the information, while using a portable document format(PDF) will probe the integrity of the content but not necessarily authorship.