July 2026
Intermediate
729 pages
33h 9m
English
Content preview from Ethical Hacking
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7.13 Practice Questions
Now that we have reached the end of our journey through the world of cryptography, it is time to put your newly acquired knowledge to work with some practice questions. I wish you every success!
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How can you ensure that the sender of a message cannot subsequently deny that they sent it?
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A. Digital signature
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B. Hash
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C. Encryption
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D. Timestamp
The correct answer is A, "Digital signature." Digital signatures use the sender's private key to sign a message that can be verified with the public key. However, if the private key falls into the wrong hands, an attacker can send messages on behalf of another person. In principle, however, digital signatures ensure the protection goal of non-repudiation. A hash, on ...
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.