CRYPTOGRAPHY AND NETWORK
SECURITY PRINCIPLES CERTIFICATION
EVALUATION 2026 FULL SOLUTION VIEW
AHEAD QUESTIONS
◉ What does confidentiality in network security mean?
Answer: Only the sender and intended receiver should understand
the message contents.
◉ What is the role of authentication in network security?
Answer: To confirm the identities of the sender and receiver.
◉ What does message integrity ensure?
Answer: That the message has not been altered during transit or
afterwards.
◉ Who are Alice, Bob, and Trudy in the context of network security?
Answer: Alice and Bob are the communicating parties, while Trudy
is the intruder who may intercept messages.
,◉ What can an intruder like Trudy do?
Answer: Eavesdrop, impersonate, hijack connections, or launch
denial of service attacks.
◉ What is symmetric key cryptography?
Answer: A method where both sender and receiver share the same
key for encryption and decryption.
◉ What is the Data Encryption Standard (DES)?
Answer: A symmetric key encryption standard using a 56-bit key
and 64-bit plaintext input.
◉ What is the Advanced Encryption Standard (AES)?
Answer: A symmetric-key encryption standard that replaced DES,
processing data in 128-bit blocks.
◉ What is public key cryptography?
Answer: A system that allows secure communication without
needing a shared secret key beforehand.
◉ What is RSA in the context of cryptography?
Answer: Rivest-Shamir-Adleman algorithm, a widely used public key
encryption method.
, ◉ What are the steps to create a public/private key pair in RSA?
Answer: Choose two large primes, compute n and z, choose e and d,
then form the public key (n,e) and private key (n,d).
◉ What is a brute force attack?
Answer: An attack method that involves searching through all
possible keys to decrypt a message.
◉ What is a known-plaintext attack?
Answer: An attack where the intruder has access to both the
plaintext and its corresponding ciphertext.
◉ What is a chosen-plaintext attack?
Answer: An attack where the intruder can encrypt plaintext of their
choice and analyze the resulting ciphertext.
◉ What is the purpose of a firewall?
Answer: To monitor and control incoming and outgoing network
traffic based on predetermined security rules.
◉ What is an Intrusion Detection System (IDS)?
SECURITY PRINCIPLES CERTIFICATION
EVALUATION 2026 FULL SOLUTION VIEW
AHEAD QUESTIONS
◉ What does confidentiality in network security mean?
Answer: Only the sender and intended receiver should understand
the message contents.
◉ What is the role of authentication in network security?
Answer: To confirm the identities of the sender and receiver.
◉ What does message integrity ensure?
Answer: That the message has not been altered during transit or
afterwards.
◉ Who are Alice, Bob, and Trudy in the context of network security?
Answer: Alice and Bob are the communicating parties, while Trudy
is the intruder who may intercept messages.
,◉ What can an intruder like Trudy do?
Answer: Eavesdrop, impersonate, hijack connections, or launch
denial of service attacks.
◉ What is symmetric key cryptography?
Answer: A method where both sender and receiver share the same
key for encryption and decryption.
◉ What is the Data Encryption Standard (DES)?
Answer: A symmetric key encryption standard using a 56-bit key
and 64-bit plaintext input.
◉ What is the Advanced Encryption Standard (AES)?
Answer: A symmetric-key encryption standard that replaced DES,
processing data in 128-bit blocks.
◉ What is public key cryptography?
Answer: A system that allows secure communication without
needing a shared secret key beforehand.
◉ What is RSA in the context of cryptography?
Answer: Rivest-Shamir-Adleman algorithm, a widely used public key
encryption method.
, ◉ What are the steps to create a public/private key pair in RSA?
Answer: Choose two large primes, compute n and z, choose e and d,
then form the public key (n,e) and private key (n,d).
◉ What is a brute force attack?
Answer: An attack method that involves searching through all
possible keys to decrypt a message.
◉ What is a known-plaintext attack?
Answer: An attack where the intruder has access to both the
plaintext and its corresponding ciphertext.
◉ What is a chosen-plaintext attack?
Answer: An attack where the intruder can encrypt plaintext of their
choice and analyze the resulting ciphertext.
◉ What is the purpose of a firewall?
Answer: To monitor and control incoming and outgoing network
traffic based on predetermined security rules.
◉ What is an Intrusion Detection System (IDS)?
