IGCSE CS Unit 2 quiz

These bytes are transmitted across a network and arrive without any errors. Does this parity block use odd or even parity?

• odd

• even

• cannot be determined

What are the benefits of using symmetric encryption?

• Uses two keys, so it's more secure than asymmetric encryption.

• Faster to compute than asymmetric encryption.

• The private key does not need to be shared.

• The public key is derived from the private key.

How can checksums help in error detection?

• Checksums are primarily used for data compression.

• Checksums help in error detection by allowing verification of data integrity through comparison of calculated values.

• Checksums can only detect changes in file size.

• Checksums are used to encrypt data for security purposes.

What are the typical uses of USB in modern devices?

• 
  Wireless internet connectivity

• 
  Video streaming to TVs

• 
  Data transfer, device charging, and connecting peripherals.

• Audio output for speakers

What is a data packet?

• A data packet is a formatted unit of data for transmission over a network.

• A data packet is a type of computer virus.

• A data packet is a physical device used for networking.

• A data packet is a software application for data analysis.

Differentiate between serial and parallel transmission.

• Serial transmission sends multiple bits at once; parallel transmission sends one bit at a time.

• Serial transmission is faster than parallel transmission; parallel transmission is slower.

• 
  Parallel transmission is used for long distances; serial transmission is for short distances.

• Serial transmission is one bit at a time; parallel transmission is multiple bits at once.

What does USB stand for?

• Universal Serial Bus

• Universal System Bus

• Universal Serial Connection

• Unified Serial Bus

What is a parity bit used for?

• To format the data for storage.

• 
  To increase data transmission speed.

• To encrypt the data being sent.

• For error detection in data transmission.

If even parity is used for error detection, what will the parity bit be?

• 0

• 1

If automatic repeat request (ARQ) is used to transmit a packet, a negative acknowledgement means

• the sender never received replay from the receiver

• the packet arrive without any errors

• the checksums did not match

• the packet was dropped by the router.