Computer Networks 0417 IGCSE "4.13 Wi-Fi and Bluetooth"

What is the carrier of data transmission for both Wi-Fi and Bluetooth?

• • A. Radio waves

• • B. Electromagnetic radiation

• • C. Infrared radiation

• • D. Ultraviolet radiation

How many frequencies does Bluetooth use?

• 79

• 80

• 81

• 82

What is the frequency that all 79 channels of Bluetooth are centered on?

• 2.45 GHz

• 5 GHz

• 79 GHz

How do devices using Bluetooth avoid interfering with other devices?

• By using the same channel as other devices.

• By using a different channel from the 79 options.

• By using a different frequency band.

• By using a different carrier wave.

What is the name of the technique used by devices using Bluetooth to minimize interference with other devices?

• Frequency modulation

• Amplitude modulation

• Spread-spectrum frequency hopping

• Phase modulation

What does Bluetooth use to create a secure wireless personal area network (WPAN)?

• Key encryption

• Public-key encryption

• Symmetric-key encryption

• Hashing algorithm

What is the maximum distance between two devices for which Bluetooth is useful?

• Less than 10 metres

• Less than 20 metres

• Less than 30 metres

• Less than 40 metres

For what type of applications is Bluetooth useful?

• High-bandwidth applications, such as streaming video.

• Low-bandwidth applications, such as sending music files from a mobile phone to a headset.

• Applications that require long-range communication.

• Applications that require high security.

Which frequency band has a faster data transfer rate but a shorter signal range in Wi-Fi?

• The 2GHz band

• The 3GHz band.

• The 4GHz band.

• The 5GHz band

What are the two most common frequency bands used by Wi-Fi?

• 2 GHz and 3 GHz

• 2.4 GHz and 5 GHz

• 2.8 GHz and 5 GHz

• • 4 GHz and 6 GHz