CPL Smart Lock & IoT Security 2 — Questions and Answers
Question 1: Which wireless protocol operates on the 908.42 MHz frequency band and is commonly used in smart locks to avoid Wi-Fi interference?
- Bluetooth Low Energy
- Zigbee
- Z-Wave (Correct answer)
- Thread
Correct answer: Z-Wave
Z-Wave operates at 908.42 MHz in North America, which avoids the crowded 2.4 GHz band used by Wi-Fi and Bluetooth.
Question 2: A customer's smart lock repeatedly disconnects from their home network. The locksmith checks and finds the lock is a Wi-Fi model placed 45 feet from the router with two walls in between. What is the most likely cause?
- Firmware is outdated
- Insufficient Wi-Fi signal strength at the lock location (Correct answer)
- The lock's battery is low
- The router's firewall is blocking the lock
Correct answer: Insufficient Wi-Fi signal strength at the lock location
Wi-Fi signal degrades with distance and obstructions; 45 feet with two walls is often enough to cause unreliable connectivity for smart locks.
Question 3: What does the term 'mesh network' mean in the context of smart lock ecosystems like Z-Wave or Zigbee?
- All devices connect directly to a central hub only
- Each device can relay signals from other devices, extending network range (Correct answer)
- Devices communicate only via Bluetooth to a gateway
- The network requires a dedicated 5 GHz band router
Correct answer: Each device can relay signals from other devices, extending network range
In a mesh network, each node (device) can act as a repeater, forwarding signals from other devices and extending the overall network range.
Question 4: Which authentication factor does a fingerprint biometric smart lock represent?
- Something you know
- Something you have
- Something you are (Correct answer)
- Something you do
Correct answer: Something you are
Biometric identifiers like fingerprints represent the 'something you are' authentication factor because they are inherent to the individual.
Question 5: A locksmith is installing a smart deadbolt that uses the Matter protocol. What is the primary advantage of Matter over older smart home protocols?
- Matter operates at a longer range than Z-Wave
- Matter provides interoperability across different smart home ecosystems (Apple, Google, Amazon) (Correct answer)
- Matter uses stronger 256-bit encryption exclusively
- Matter eliminates the need for a hub or bridge device
Correct answer: Matter provides interoperability across different smart home ecosystems (Apple, Google, Amazon)
Matter is an open-source, IP-based connectivity standard designed to ensure smart home devices work seamlessly across different platforms like Apple Home, Google Home, and Amazon Alexa.
Question 6: When a smart lock uses 'rolling codes' (also called hopping codes) for key fob authentication, what security problem does this solve?
- It prevents physical lock picking
- It prevents replay attacks where an intercepted code is reused (Correct answer)
- It eliminates the need for encryption
- It extends the battery life of the key fob
Correct answer: It prevents replay attacks where an intercepted code is reused
Rolling codes generate a new authentication code for each use, so an intercepted code cannot be replayed to gain unauthorized access.
Question 7: A CPL is asked to recommend a smart lock for a client who wants remote access but lives in an area with frequent internet outages. Which feature is most critical to recommend?
- Cloud-only authentication
- Local processing with offline access codes as backup (Correct answer)
- Facial recognition
- IFTTT integration
Correct answer: Local processing with offline access codes as backup
A lock with local processing capability and offline access codes ensures the lock remains functional even when internet connectivity is unavailable.
CPL Smart Lock & IoT Security 2
Which wireless protocol operates on the 908.42 MHz frequency band and is commonly used in smart locks to avoid Wi-Fi interference?