IGCSE Computer Science Quiz: Error Checking Methods & Encryption

What is the purpose of error-checking methods in computer technology?

• To compress data for storage

• To encrypt sensitive information

• To detect and correct errors

• To enhance data transmission speed

What does parity checking use to determine if data has been corrupted?

• An echo check

• A checksum

• A check digit

• A parity bit

In even parity, how many bits of 1s should there be in a byte?

• An odd number

• At least 3 bits

• An even number

• Exactly 5 bits

What happens if the recalculated checksum does not match the sent checksum?

• The data is accepted as correct

• The data is automatically corrected

• A request is made to re-send the block of data

• The data is discarded

What is an echo check?

• A method to encrypt data

• A method to correct errors automatically

• A method to calculate checksums

• A method to send data back to the sender for comparison

What is a check digit used for?

• To encrypt data

• To ensure a range of numbers has been entered correctly

• To calculate checksums

• To detect transmission errors

What does Automatic Repeat Request (ARQ) use to ensure data is received correctly?

• Encryption keys

• Acknowledgement and timeout

• Checksum values

• Parity bits

What is symmetric encryption?

• Using a single secret key for both encryption and decryption

• Using two different keys for encryption and decryption

• A method that uses public keys only

• A method that does not require a key

What is the main advantage of asymmetric encryption?

• It does not require any keys

• It provides a higher level of security

• It uses a single key for encryption

• It is faster than symmetric encryption

What is cryptography?

• The process of transmitting data

• The process of scrambling readable text into unreadable text

• The process of compressing data

• The process of storing data securely