Here are the top 50 commonly asked questions in IOT interviews. Whether you’re just starting your preparation or need a quick refresher, these questions and answers will help you tackle your interview with confidence.
Basic IOT Interview Questions with Answers
1. What is IoT?
IoT stands for Internet of Things. It is a network of devices (sensors and actuators) that collect and share data and communicate over the internet with minimal human intervention.
2. What are the different development boards used in IoT systems?
Microcontroller-based boards, System on Chip (SOC) boards, and Single-board Computers (SBC) are the different types of development boards used in IoT systems. Examples of these boards are Arduino, Raspberry Pi, Particle Photon, Banana Pi, Omega 2, etc.
3. What technologies are closely related to IoT?
Technologies that are closely related to IoT are Machine to Machine (M2M) communications, Cyber-Physical Systems (CPS), Internet of Everything (IoE), Industry 4.0, and Web of Things (WoT).
4. What are the two categories of IoT?
Industrial IoT and Consumer IoT are the two categories of IoT.
5. What are the key technologies for IoT?
The key technologies for IoT are Embedded Systems, System Integration, Security and Privacy, Knowledge Aggregation, Standards, Sensor Networks, Communication, Cloud Computing, Discovery Services, and Nano-electronics,
6. What are the leading connectivity technologies used in IoT systems?
The different connectivity technologies used in IoT systems are RFID, Bluetooth, BLE (Bluetooth Low Energy), IEEE 802.15.4, ZigBee, Z-Wave, 6LoWPAN, and NFC.
7. Which Cloud Simulators are used while developing IoT projects?
Cloud Simulators that are used while developing IoT projects are CloudAnalyst, GroundSim, CloudSim, GreenCloud, and iCanCoud.
8. What are the constituents of an IoT Smart Living system?
Smart Homes, e-Health, Servicing Agencies, Water Management, Agriculture, Waste Management, Contactless Transaction, Localities, Energy Management, and Population are the constituents of an IoT Smart Living system.
9. What are the technological processes involved in IoT?
The various technological processes involved in IoT are Data Collection, Data Transmission, Data Storage, and Data Processing.
10. What are the different components involved in collecting information in an IoT Smart Parking system?
Sensors, sensor networks, parking meters, and crowdsensing are the different components involved in collecting information in an IoT Smart Parking system.
11. What is the main aim of IoT?
Interconnection of smart things at a global scale, such that they can be identified uniquely and are interoperable, is the main aim of IoT.
12. How are Industry 4.0 and IIoT related to IoT?
The intersection of IoT and Industry 4.0 constitutes IIoT. IIoT is not the same as IoT.
13. What are the different functions provided by the devices of an IoT system?
An IoT system comprises of devices that provide the functions like sensing, actuation, monitoring, and control.
14. Who coined the term Internet of Things and when?
Kevin Ashton coined the term Internet of Things in 1999.
15. Which is the first IoT device that was recognized in the world?
Coca-Cola vending machine is the first IoT device that was recognized in the world.
16. What is a thing in the context of IoT?
A thing is any device that can be uniquely identified and is connected to a network over the internet through which it can transfer and receive data. Things may include objects, machines, people, plants, vehicles, etc.
17. Why is a microcontroller needed in IoT?
In an IoT system, a microcontroller acts as the brain of the entire system. It is needed to link all the other components of the system with each other.
18. Why is an actuator needed in IoT?
An actuator is an entity of IoT that is needed to perform some physical, mechanical action.
19. What are the different types of sensors used in IoT?
The various types of sensors used in IoT are temperature sensors, pressure sensors, proximity sensors, smoke sensors, gas sensors, camera and sensors, infrared sensors, level sensors, accelerometers, gyroscopes, optical sensors, humidity sensors, sound sensors, and chemical sensors.
20. What are the ABCDs of IoT?
The ABCDs of IoT are Application, Backend, Connectivity, and Devices.
Intermediate IOT Interview Questions with Answers
21. What are soft actuators?
Actuators that are intended to handle delicate objects like manipulating the internal organs in bio-medicine, are known as soft actuators.
22. What are the challenges faced by IoT?
Security, scalability, interoperability, energy efficiency, complexity management, interfacing, data storage, and data modeling and analysis are the challenges faced by IoT.
23. What are some of the discovery-based IoT protocols?
Some discovery-based IoT protocols are Physical Web, DNS-SD, and mDNS.
24. What are some of the identification-based IoT protocols?
Some identification-based IoT protocols are Ipv6, uCode, and EPC.
25. What are some of the data-based IoT protocols?
Some data-based IoT protocols are CoAP, MQTT, and AMQP.
26. What are some of the communication-and-transport-based IoT protocols?
Some communication-and-transport-based IoT protocols are BLE, Wifi, and Z-Wave.
27. What are the four stages of the Secure MQTT algorithm?
The four stages of the SMQTT algorithm are setup, encryption, publish, and decryption.
28. What are the constituent layers of the CoAP architecture?
The constituent layers of the CoAP architecture are Messaging and Request-Response.
29. What are the core XMPP technologies?
Core, Jingle, BOSH, PubSub, and Multi-user Chat are the core XMPP technologies.
30. What are the different types of AMQP frames?
The nine different types of AMQP frames are Open, Begin, Attach, Transfer, Flow, Disposition, Detach, End, and Close.
31. What are the four AMQPP Exchanges?
Direct, Fan-out, Topic, and Header are the four AMQPP exchanges.
32. What are the IEEE 802.15.4 device types?
IEEE 802.15.4 constitutes two types of devices, Full Function Device (FFD) and Reduced Function Device (RFD).
33. What are the different types of IEEE 802.15.4 frames?
The different types of IEEE 802.15.4 frames are beacon, MAC, command, acknowledgement, and data.
34. What are the important components of ZigBee?
The important components of ZigBee are ZigBee Device Object (ZDO) and Application Support Sub-layer (APS).
35. What are the different layers of ZigBee protocol architecture?
The different layers of ZigBee protocol architecture are physical layer, MAC layer, network layer, application support sublayer, and application framework.
36. Why was the HART protocol developed?
HART (Highway Addressable Remote Transducer) protocol was developed to implement networked smart field devices.
37. What is the main difference between wired HART and unwired HART?
The main difference between wired HART and unwired HART is that the former doesn’t have a network layer, whereas the latter has a network layer.
38. What are the types of NFC devices? On which principle do they operate?
NFC devices are of two types, active and passive. They work on the principle of magnetic induction.
39. What are the modes of operation of NFC?
Peer-to-peer, read-write, and card emulation are the modes of operation of NFC.
40. What are the different stages of connection establishment in Bluetooth technology?
The stages of connection establishment in Bluetooth technology are inquiry, paging, and connection.
41. What are the different modes of Bluetooth-connected devices?
Active, sniff, hold, and park are the different modes of Bluetooth-connected devices.
42. What are the modulation technique and the encoding technique used by Z-Wave?
Gaussian Frequency Shift Keying modulation and Manchester channel encoding are used by Z-Wave.
43. What are the components of a sensor node?
A sensor node comprises of the following components, Location Finding Unit, Sensing Unit, Transceiver, ADC, Processor, Storage, and Power.
44. What are the communication options available to nano-devices?
The communication options available to nano-devices are molecular communication and electromagnetic communication.
45. What is the classification of coverage problems in static Wireless Sensor Networks?
The coverage problems in static Wireless Sensor Networks can be classified as point coverage, area coverage, and barrier coverage.
46. What is the full form of MANET? What are the self-CHOP properties of MANET?
MANET stands for Mobile Ad Hoc Network. The self-CHOP properties of MANET are self-Configure, self-Help, self-Optimize, and self-Protect.
47. What are the components of Mobile Wireless Sensor Networks?
The components of Mobile Wireless Sensor Networks are mobile sensor nodes, mobile sink, and data mules.
48. What are the different M2M sensor node types?
The different M2M node types are low-end, mid-end, and high-end.
49. What are the components of Software Defined Networks (SDNs)?
The components of SDNs are applications, controller, hardware switches, flow-rules, and APIs.
50. What are the different approaches to build a Software-Defined Wireless Sensor Network?
Sensor OpenFlow, Soft-WSN, and SDN-WISE are the approaches available to build a Software-Defined WSN.
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