Questions and Answers

(a) Define the Internet of Things (IoT) The Internet of Things (IoT) refers to a network of interconnected physical devices that are embedded with sensors, processors, software, and communication technologies to collect, exchange, and process data over the Internet without requiring direct human intervention. IoT devices can sense environmental conditions, communicate data, and perform intelligent actions automatically. Examples include • smart home devices • wearable health monitors • industrial automation systems • smart city infrastructure (b) Explain the significance of IoT in modern technology IoT plays a major role in modern technology because it enables • automation • real-time monitoring • intelligent decision-making • remote control • predictive maintenance • efficient resource management Significance of IoT Area Importance Smart Homes Automation of lighting, temperature, security Healthcare Remote patient monitoring Industry Industrial automation and predictive maintenance Agriculture Smart irrigation and crop monitoring Smart Cities Traffic management and energy optimisation IoT improves • operational efficiency • productivity • convenience • safety • data-driven decision-making (c) Discuss the key components of an IoT ecosystem The main components of an IoT ecosystem are Component Description Sensors Collect environmental data Actuators Perform actions based on commands Processor/Microcontroller Processes sensor data Communication Network Transfers data between devices Gateway Connects local devices to cloud Cloud Platform Stores and analyses data User Interface Allows users to monitor/control system A typical IoT system follows Sensor → Processor → Network → Cloud → User/Application (d) Identify security challenges associated with IoT devices Major IoT security challenges include 1. Weak Authentication Many IoT devices use • default usernames • weak passwords This allows unauthorized access. 2. Insecure Communication Data transmitted without encryption can be intercepted. 3. Lack of Software Updates Outdated firmware may contain vulnerabilities.4. Physical Tampering Attackers may physically access remote devices. 5. Malware and Botnets IoT devices can be infected and used in: • DDoS attacks • botnets (e) Propose approaches to mitigate IoT security risks Security Risk Mitigation Weak passwords Strong authentication & MFA Unencrypted data Use TLS/SSL encryption Firmware vulnerabilities Regular updates/patching Unauthorized access Access control mechanisms Malware IDS/IPS and firewalls Additional measures • secure boot • VPN usage • device certificates • network segmentation (f)(i) Ethical concerns associated with IoT Major ethical concerns include • privacy invasion • unauthorized surveillance • misuse of personal data • lack of user consent • excessive data collection (f)(ii) ExamplesExamples include • smart speakers recording conversations • wearable devices tracking personal health data • smart cameras monitoring individuals without consent (f)(iii) Addressing ethical concerns professionally Ethical concerns can be addressed through • transparent privacy policies • informed user consent • data minimization • strong data protection policies • regulatory compliance (GDPR etc.) Organizations must ensure • accountability • responsible data handling • secure storage of user data (a) Describe the role of sensors in IoT systems Sensors detect physical or environmental conditions and convert them into electrical or digital signals. Sensors are used to measure • temperature • humidity • pressure • motion • light • sound They act as the “input devices” of IoT systems. (b) List types of sensors used in IoT Examples include • temperature sensors • humidity sensors • pressure sensors • gas sensors • ultrasonic sensors • motion sensors • light sensors (c) Explain how sensors interact with IoT devices Sensors collect environmental data and send signals to • microcontrollers • processors The processor: • interprets data • processes information • sends data through communication modules Example Temperature Sensor → Arduino → Wi-Fi Module → Cloud(d) Importance of connectivity and networks in IoT Connectivity enables IoT devices to • exchange data • communicate remotely • access cloud services • support automation Without connectivity • devices cannot interact • remote monitoring becomes impossible IoT networks support • scalability • real-time communication • intelligent decision-making (e) Compare wireless technologies used in IoT Technology Range Power Speed Use Case Wi-Fi Medium High High Smart homes Bluetooth/BLE Short Low Medium Wearables ZigBee Medium Very Low Low Sensor networks LoRaWAN Long Very Low Very Low Smart agriculture NB-IoT Very Long Low Medium Smart city Lecture notes compare LoRa, ZigBee, Bluetooth and Wi-Fi for IoT communication. (f) Strategies to extend battery life Methods include • sleep modes • duty cycling • event-driven communication • reducing transmission frequency • low-power communication protocols • energy-efficient routing Lecture notes explain the importance of sleep modes and deep sleep in ESP8266 systems. (a) Explain encryption in IoT Encryption converts readable data into unreadable ciphertext using an encryption key. It protects • confidentiality • integrity • privacy Encryption prevents attackers from reading transmitted data. (b) Common encryption techniques in IoT Technique Type Usage AES Symmetric Fast IoT encryption RSA Asymmetric Key exchange ECC Asymmetric Lightweight security TLS/SSL Secure communication Internet communication (c) Implementing secure communication protocol Secure IoT communication can be implemented using • MQTT over TLS • HTTPS • CoAP with DTLS Steps: 1. Authenticate devices 2. Encrypt communication 3. Use secure certificates 4. Apply access control 5. Regularly update firmware (d) XOR Encryption Code Example Python Example data = "TEMP25" key = 5 encrypted = "" for char in data: encrypted += chr(ord(char) ^ key) print("Encrypted:", encrypted) decrypted = "" for char in encrypted: decrypted += chr(ord(char) ^ key) print("Decrypted:", decrypted) Explanation • XOR compares binary bits. • Same key is used for encryption and decryption. • Without the key, data becomes difficult to interpret. This is a simple demonstration of encryption principles in IoT systems.(a) Define a Wireless Sensor Network (WSN) A Wireless Sensor Network (WSN) is a self-configured wireless network of sensor nodes used to monitor environmental or physical conditions and communicate data wirelessly to a central system. (b) How WSNs improve IoT efficiency WSNs improve IoT systems through • real-time monitoring • remote sensing • automation • reduced wiring • scalability • distributed sensing (c) Three WSN topologies 1. Star topology 2. Mesh topology 3. Hybrid topology These are explained in the lecture notes. (d) Impact of topologies on performance Topology Impact Star Simple but central hub failure risk Mesh Reliable and fault tolerant Hybrid Scalable and flexible (e) Advantages and disadvantages of WSN Advantages 1. Low wiring 2. Flexible deployment 3. Remote monitoring 4. Scalability