What is the primary purpose of the Diffie-Hellman key exchange protocol?

To compress data before transmission

To allow two parties to securely agree on a shared secret key over an insecure channel

To encrypt data using a public key

A company is setting up a VPN between two sites. They want to use a key exchange that is resistant to man-in-the-middle attacks. Which protocol should they use?

Diffie-Hellman with pre-shared keys

Diffie-Hellman without authentication

Diffie-Hellman with certificates

RSA key exchange without certificates

A software company is designing a system to verify the integrity of log files. They need to detect any modification, but they also want to avoid storing a large hash for every log entry. Which approach balances security and storage efficiency?

Encrypt each log entry with a symmetric key and store the key with the logs.

Use a hash chain: store the hash of each log entry combined with the previous hash.

Store an MD5 hash for each log entry in a separate database.

Use a digital signature for each log entry and store the signatures in a public ledger.

Two servers need to establish a secure session using symmetric encryption. They want to use a key exchange method that also provides authentication to prevent man-in-the-middle attacks. Which approach should they use?

Diffie-Hellman without authentication

Pre-shared key sent over the network

RSA key exchange with certificates

Using a simple hash of a password

What is a key property of a cryptographic hash function?

It produces a fixed-size output regardless of input length.

It always produces a unique output for every possible input.

It uses a secret key to encrypt data.

It is reversible, allowing the original data to be recovered.

EC-CouncilNetwork Defense Essentials

Domain 6Objective 1

Cryptographic Techniques and Algorithms NDE Practice Questions (Page 5)

Part of the Cryptography, PKI, and Data Security domain, which makes up ~15% of our current practice bank.

39questions here

8free pages

6concepts

Questions 21–25

21foundation · easy
What is the primary purpose of the Diffie-Hellman key exchange protocol?
Select an answer first
22application · medium
A company is setting up a VPN between two sites. They want to use a key exchange that is resistant to man-in-the-middle attacks. Which protocol should they use?
Select an answer first
23expert · hard
A software company is designing a system to verify the integrity of log files. They need to detect any modification, but they also want to avoid storing a large hash for every log entry. Which approach balances security and storage efficiency?
Select an answer first
24application · medium
Two servers need to establish a secure session using symmetric encryption. They want to use a key exchange method that also provides authentication to prevent man-in-the-middle attacks. Which approach should they use?
Select an answer first
25foundation · easy
What is a key property of a cryptographic hash function?
Select an answer first

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