{{asɛmtiNe Ɔkyerɛwfo}} | Nhomakorabea | Nneɛma a ɛma wotumi yɛ ade

1

A student wants to send a secure message to their friend for the first time. They have never communicated before. Which statement best explains how asymmetric encryption helps in this situation?

It requires both users to meet in person to exchange a shared key

It prevents any need for keys at all

It allows the sender to use the receiver’s public key without sharing a secret ahead of time

It uses the same key for both encryption and decryption

1

A company wants to receive secure messages from customers online. What must the company do first?

Use a single shared password for all users

Wait for customers to send their own keys first

Generate a key pair with a public and private key

Share its private key with customers

1

Two keys are generated together as part of asymmetric encryption. What best describes how these keys are related?

They are identical copies used for backup

They are both public and used interchangeably

They are mathematical inverses, where one reverses the other

They are unrelated and used randomly

1

A message is encrypted using a public key. Which key must be used to decrypt it?

A randomly generated key

Any public key from the system

The same public key

The matching private key

1

A developer encrypts a file using a private key. Which key can decrypt it?

A symmetric key

The same private key

Any private key

The matching public key

1

A user wants others to be able to send them secure messages. Which key should they share publicly?

Their public key

A randomly generated key

Both keys together

Their private key

1

An attacker gains access to a company’s private key. What is the most appropriate response?

Continue using the same key pair since the public key is still secure

Delete the key pair and generate a new one

Switch to symmetric encryption only

Only change the public key

1

Why must a private key be kept secret?

Because it is needed to generate public keys

Because it is less complex than the public key

Because it is used to encrypt all outgoing messages

Because anyone with it can decrypt secure messages

1

A student says, “It’s safe to share both keys as long as people don’t misuse them.” What is the best correction?

Neither key should ever be shared

Only the private key should be shared

Both keys should always be shared publicly

Only the public key should be shared; the private key must remain secret

1

Which scenario correctly describes sending a secure message using asymmetric encryption?

The sender encrypts the message with the receiver’s private key

The sender encrypts the message with the receiver’s public key

The sender uses no key and sends the message directly

The sender encrypts the message with their own private key

1

An attacker intercepts an encrypted message but does not have access to the private key. What can they do?

Decrypt the message using the public key

Decrypt the message using any available key

They cannot decrypt the message

Read the message directly

1

What is the keyspace of a 5-bit encryption key?

10 possible keys

32 possible keys

25 possible keys

64 possible keys

1

A system uses an 8-bit key. How many possible keys exist?

128

256

512

1024

1

On average, how many guesses would it take to break a 6-bit key using brute force?

6 guesses

32 guesses

64 guesses

128 guesses

1

Why does increasing key length improve security?

It reduces the need for private keys

It increases the number of possible keys exponentially

It allows the same key to be reused safely

It makes the encryption algorithm simpler

1

A hacker is trying to guess a key. Which key would take the longest to crack?

A 16-bit key

All take the same time

A 4-bit key

An 8-bit key

1

A company increases its key length from 128 bits to 256 bits. What is the main benefit?

Faster encryption speeds

Smaller keyspace

Greater security due to more possible keys

Easier key sharing

1

What is one drawback of using very long encryption keys?

They are easier to guess

They require more processing time

They reduce security

They cannot be used for encryption

1

Why do organizations update recommended key lengths over time?

Computers become faster at guessing keys

Keys become easier to remember

Encryption algorithms stop working

Public keys expire automatically

1

Which comparison is valid when determining which key is more secure?

RSA 2048-bit vs AES 256-bit

AES 128-bit vs AES 256-bit

AES vs all other algorithms

AES 128-bit vs RSA 2048-bit

1

A student claims that a 2048-bit RSA key is always stronger than a 256-bit AES key because it is longer. What is the best response?

The comparison is valid because both use binary keys

The student is correct because RSA is always more secure

The student is correct because longer always means stronger

The comparison is invalid because different algorithms cannot be directly compared

1

An attacker is trying to guess a key randomly. What is the expected number of guesses needed to find the correct key?

One guess

Twice the number of possible keys

Half of all possible keys

All possible keys

1

A system uses a very short key to speed up performance. What is the biggest risk?

Attackers can guess the key more easily

The system will stop working

The key will expire quickly

Messages cannot be decrypted

1

Two systems use different encryption algorithms. Why can’t their key lengths be directly compared?

They use different types of data

One uses public keys and the other does not

They have different key generation speeds

Key length only has meaning within the same algorithm

AP Cybersecurity: 5.4A - CFUs

AP Cybersecurity: 5.4A - CFUs

A student wants to send a secure message to their friend for the first time. They have never communicated before. Which statement best explains how asymmetric encryption helps in this situation?

A company wants to receive secure messages from customers online. What must the company do first?

Two keys are generated together as part of asymmetric encryption. What best describes how these keys are related?

A message is encrypted using a public key. Which key must be used to decrypt it?

A developer encrypts a file using a private key. Which key can decrypt it?

A user wants others to be able to send them secure messages. Which key should they share publicly?

An attacker gains access to a company’s private key. What is the most appropriate response?

Why must a private key be kept secret?

A student says, “It’s safe to share both keys as long as people don’t misuse them.” What is the best correction?

Which scenario correctly describes sending a secure message using asymmetric encryption?

An attacker intercepts an encrypted message but does not have access to the private key. What can they do?

What is the keyspace of a 5-bit encryption key?

A system uses an 8-bit key. How many possible keys exist?

On average, how many guesses would it take to break a 6-bit key using brute force?

Why does increasing key length improve security?

A hacker is trying to guess a key. Which key would take the longest to crack?

A company increases its key length from 128 bits to 256 bits. What is the main benefit?

What is one drawback of using very long encryption keys?

Why do organizations update recommended key lengths over time?

Which comparison is valid when determining which key is more secure?

A student claims that a 2048-bit RSA key is always stronger than a 256-bit AES key because it is longer. What is the best response?

An attacker is trying to guess a key randomly. What is the expected number of guesses needed to find the correct key?

A system uses a very short key to speed up performance. What is the biggest risk?

Two systems use different encryption algorithms. Why can’t their key lengths be directly compared?

A student wants to send a secure message to their friend for the first time. They have never communicated before. Which statement best explains how asymmetric encryption helps in this situation?

A company wants to receive secure messages from customers online. What must the company do first?

Two keys are generated together as part of asymmetric encryption. What best describes how these keys are related?

A message is encrypted using a public key. Which key must be used to decrypt it?

A developer encrypts a file using a private key. Which key can decrypt it?

A user wants others to be able to send them secure messages. Which key should they share publicly?

An attacker gains access to a company’s private key. What is the most appropriate response?

Why must a private key be kept secret?

A student says, “It’s safe to share both keys as long as people don’t misuse them.” What is the best correction?

Which scenario correctly describes sending a secure message using asymmetric encryption?

An attacker intercepts an encrypted message but does not have access to the private key. What can they do?

What is the keyspace of a 5-bit encryption key?

A system uses an 8-bit key. How many possible keys exist?

On average, how many guesses would it take to break a 6-bit key using brute force?

Why does increasing key length improve security?

A hacker is trying to guess a key. Which key would take the longest to crack?

A company increases its key length from 128 bits to 256 bits. What is the main benefit?

What is one drawback of using very long encryption keys?

Why do organizations update recommended key lengths over time?

Which comparison is valid when determining which key is more secure?

A student claims that a 2048-bit RSA key is always stronger than a 256-bit AES key because it is longer. What is the best response?

An attacker is trying to guess a key randomly. What is the expected number of guesses needed to find the correct key?

A system uses a very short key to speed up performance. What is the biggest risk?

Two systems use different encryption algorithms. Why can’t their key lengths be directly compared?