Sec 9.9 Hashing

You have just downloaded a file. You create a hash of the file and compare it to the hash posted on the website. The two hashes match. What do you know about the file?

Your copy is the same as the copy posted on the website.

Which of the following best describes high amplification when applied to hashing algorithms?

A small change in the message results in a big change in the hash value.

When two different messages produce the same hash value, what has occurred?

Collision

Which of the following is used to verify that a downloaded file has not been altered?

Hash A hash is a function that takes a variable-length string (message) and compresses and transforms it into a fixed-length value. Hashes ensure the data integrity of files and messages in transit.

A birthday attack focuses on what?

Hashing algorithms Birthday attacks exploit the probability that two messages using the same hash algorithm will produce the same message digest.

Hashing algorithms are used to perform what activity?

Hashing algorithms are used to create a message digest to ensure that data integrity is maintained.

Which of the following is the weakest hashing algorithm?

MD5 is the weakest hashing algorithm. It produces a message digest of 128 bits. The larger the message digest, the more secure the hash. SHA-1 is more secure because it produces a 160-bit message digest.

Which of the following does not or cannot produce a hash value of 128 bits?

SHA-1

Which of the following is the strongest hashing algorithm?

SHA-1 SHA-1 is the strongest hashing algorithm. SHA-1 generates a message digest of 160 bits.

SHA-1 uses which of the following bit length hashing algorithms?

only 160 bits-It is capable of producing 2160 different combinations.