Cryptography

What is the primary purpose of cryptography?

• a) Compressing data

• b) Protecting information

• c) Speeding up communication

• d) Storing files

Which type of encryption uses a single key for both encryption and decryption?

• a) Symmetric encryption

• b) Asymmetric encryption

• c) Hashing

• • d) Digital signatures

What is the role of encryption in messaging apps like WhatsApp?

• a) Message compression

• b) End-to-end encryption

• c) Data storage

• d) Message deletion

Which protocol is used to secure online payments?

• a) FTP

• b) HTTP

• c) SSL/TLS

• d) DNS

What does hashing ensure?

• a) Data confidentiality

• b) Data integrity

• c) Fast file transfer

• d) Secure key exchange

What is the difference between symmetric and asymmetric encryption?

• a) Symmetric uses two keys, while asymmetric uses one key.

• b) Symmetric uses one key, while asymmetric uses a key pair.

• c) Asymmetric is faster than symmetric encryption.

• d) Symmetric is only used for small files.

What is a Certificate Authority (CA) responsible for?

• a) Generating keys

• b) Issuing and managing digital certificates

• c) Encrypting emails

• d) Storing public keys

What does a digital certificate typically include?

• a) A hashed message

• b) The entity's public key and identity information

• c) A symmetric encryption key

• d) The entity's private key

Which hashing algorithm is widely used for blockchain integrity?

• a) MD5

• b) SHA-256

• c) RSA

• d) AES

Why is key distribution a challenge in symmetric encryption?

• a) Keys must be exchanged securely between parties.

• b) It requires complex mathematical calculations.

• c) It cannot encrypt large files.

• d) It is too slow for real-time communication.