Most Asked IoT Interview Questions and Answers

In this article, we will go through 40 of the most important interview questions based on Linux. Then, we shall cover some of the frequently asked questions on IoT. This article is perfect for newbies and experts, so stay focused as we slowly advance through the 40 questions.

Q1. What is IoT?

IoT is the abbreviation for the Internet of Things. It is a network of devices communicating with each other and constantly sending, receiving, storing, and analyzing data without any human intervention.

Q2. What is an Internet Protocol?

An internet protocol is a set of rules that specifies how the data gets sent to the internet. The protocol enables the communication of IoT devices over a network.

Q3. What are the basic components of IoT?

IoT has four basic components. They are sensors, connectivity, data processing, and User Interface(UI).

Q4. Briefly explain the sensor component of an IoT system.

Sensors are devices that convert information obtained in the outer world into data for analysis. These include data regarding the process or environmental surroundings like temperature, fluid flow in the pipe, air quality, etc.

Q5. Briefly explain the connectivity component of an IoT system.

The connectivity component enables all the devices in an IoT ecosystem to communicate with each other (including the cloud). The way a device is connected to the cloud depends on various factors, like the data collected and how it will be processed.

Q6. Explain the data processing component of an IoT system.

Data processing is the process of the cloud converting the raw data obtained from the sensors into a machine-readable form so that the IoT device knows what should happen next. The data collected by the sensors is in analogue form. The cloud then processes this data to convert it into digital form.

Q7. Explain the User Interface component of an IoT system.

The UI gives the output to the user after the cloud processes the data. The User Interface also lets users control an IoT system. A UI lets users interact with an IoT device.

Q8. List a few disadvantages of IoT

Some disadvantages of IoT are:

a. Security: Since IoT stores a lot of sensitive information, hackers can attack an IoT system to access this data and maybe even expose it.

b. Dependence on the Internet: IoT depends way too much on Internet connectivity. IoT devices fail to work without a stable internet connection, and the tasks remain incomplete.

c. Malware: If a cybercriminal puts malware in one IoT device, the entire system becomes corrupt because they are all interconnected together in a network.

d. Lack of International Standard: Since there is no set of international IoT standards to match compatibility there, problems occur in communication between manufacturers of different domains.

Q9. What are the layers of the IoT protocol stack?

The four layers of the IoT protocol stack are sensing and information, network connectivity, information processing layer, and application layer.

Q10. What is IIoT?

IIoT is short for “Industrial Internet of Things”. It is an application of IoT that is used in the industrial sector as it supports industry-oriented applications. IIoT is the use of IoT sensors and devices to enhance manufacturing and industrial processes. IIoT is sometimes referred to as “industry 4.0”.

Q11. What is IoMT?

IoMT is the abbreviation for “Internet of Medical Things”. IoMT is the use of IoT sensors and devices that connect to healthcare IT systems to provide better healthcare to patients. Sometimes, IoMT is also referred to as healthcare IoT. IoMT is an application of IoT in the healthcare sector to aid doctors in giving better care and treatments to the sick.

Q12. What are the differences between IoT and IIoT?

IoT	IIoT
Abbreviation for Internet of Things.	Short for Industrial Internet of Things.
Human-centric model	Machine-centric model
Supports customer-oriented applications.	Supports industry-oriented applications.
Communication is done via wireless devices.	Communication is done via both wireless and wired devices
The quality of data is medium to high.	The quality of data is high to very high.
Not so severe criticality	Severe criticality

Q13. Give three advantages of IoT

a. Monitoring: IoT enables remote monitoring, where a person can monitor data from a different place.

b. Automation: IoT helps in automation as it can perform pre-programmed tasks once all the triggers are met.

c. Resource Utilisation: IoT manages and optimises the usage of resources. This is excellent for reducing waste and offering cost-effective and feasible methods for complicated problems.

Q14. What is Arduino?

Arduino is a free, open-source, and easy-to-use electronics platform that has a microcontroller to read input from sensors to control the motors programmatically.

Q15. Give a few examples of sensors used in IoT.

Some of the most used sensors in IoT are smoke sensors, temperature sensors, pressure sensors, motion detection sensors, gas sensors, proximity sensors, and IR sensors.

Q16. List 3 domains in which IoT is used.

a. IIoT: IIoT is the use of IoT sensors and devices to enhance manufacturing and industrial processes.

b. IoMT: IoMT is the use of IoT sensors and devices that connect to healthcare IT systems to provide better healthcare to patients.

c. CIoT: It is an application of IoT where an interconnected system of physical and digital objects is personally used by a consumer.

Q17. What is IoT Security?

The part of IoT that deals with the protection of the IoT system, servers, networks, and physical devices is IoT security. IoT security involves various tools, strategies, and methods that help users to safeguard their IoT ecosystems.

Q18. Explain a few preventive methods to reduce the number of cyberattacks on IoT devices.

a. End-to-end Encryption: In an IoT ecosystem, data transfers happen when one device communicates with another by using a protocol. To make sure that the communication is safe, we can make use of end-to-end encryption.

b. Selecting a Cybersecurity Provider: Another preventive method is to select an excellent antivirus provider or an expert cybersecurity provider to protect your IoT system against threats and vulnerabilities.

c. NAC: NAC is short for Network Access Control. It recognises all the devices in a certain network and helps in monitoring and tracking devices easily.

d. Segmentation: The network of each IoT device can be segmented such that it connects to the internet and can limit access to the business network. However, one must still monitor the network for unidentified access.

Q19. What are some ways in which cybercriminals can create cyberattacks on IoT devices?

a. Malware: Malware is the method most used by cybercriminals to attack IoT systems. Hackers use IoT botnet malware, which is the most popular variant, to gain access to private IoT ecosystems.

b. Device Mismanagement: Users give room for cybercriminals to breach IoT systems by giving poor passwords, neglecting updates, not configuring the device properly, etc.

c. Cybersecurity Escalation: DDoS attacks often use infected devices, and one hacked device can give access to other web servers and networks.

Q20. Explain pulse width modulation.

Pulse Width Modulation (PWM) is a variation of how much time the signal is high in an analogue fashion. This signal can either be high or low, and the user can even change the proportion of the time.

Q21. List a few uses of pulse width modulation in IoT.

There are many applications of PWM in IoT. Some of them include controlling the speed of a DC motor, controlling the direction of a servo motor, Dimming LED, etc.

Q22. What is AMQP?

AMQP is short for Advanced Message Queuing Protocol. It is an open protocol used for more message-oriented middleware. The AMQP internet protocol offers security and interoperability. It is also very reliable, even at a distance or over poor networks.

Q23. What is CoAP?

CoAP is short for “Constrained Application Protocol”. This protocol was designed to work with HTTP-based IoT systems. CoAP depends on UDP (User Datagram Protocol). CoAP is often used for machine-to-machine applications as it enables constrained devices to join an IoT environment, even with low bandwidth.

Q24. Give a brief explanation of the LoRa Internet protocol.

LoRa is short for “long-range”. It is a noncellular wireless technology that offers long-range communication capabilities. It packs low-power and secure data transmission for machine-to-machine applications and IoT deployments.

Q25. What are messaging protocols?

IoT communication protocols are session layer protocols that help in managing the connection between two endpoints of a network by controlling data between sender and receiver.

Q26. Give a few examples of messaging protocols.

There are many messaging protocols. Some of them are MQTT (Message Queuing Telemetry Transport), AMQP (Advanced Message Queuing Protocol), CoAP (Constrained Application Protocol), DDS (Data Distribution Service), XMPP (Extensible Messaging and Presence Protocol), and SMQTT (Secure Message Queue Telemetry Transport).

Q27. Give a few examples of communication protocols.

There are many messaging protocols. Some of them are Bluetooth Low Range, Wi-Fi (Wireless-Fidelity), Zigbee, Nb-IoT (“Narrowband IoT), and Thread.

Q28. Give a few examples of network layer protocols.

There are many messaging protocols. Some of them are ARP (Address Resolution Protocol), RARP (Reverse Address Resolution Protocol), ICMP (Internet Control Message Protocol), CARP (Caching Array Routing Protocol), 6LoWPAN (IPv6 over Low Power Wireless Personal Area Network).

Q29. What are the advantages of the DDS protocol?

The advantages of using the DDS network protocol are as follows:
a. Simple architecture that supports “auto-discovery.”
b. DDS is both effective and scalable.
c. It used transport bandwidth.
d. It has dedicated data delivery.

Q30. What are the advantages of Wi-Fi?

The advantages of using Wi-Fi as an internet protocol are

a. Privacy and Security: The reason why Wi-Fi is a powerful technology in modern security and access control systems for small and large buildings and organisations is because of its encrypted and secure data communication.

b. Easy to install: It makes use of simple steps to connect devices and easy-to-install processes that deliver user convenience and easy usage.

c. Fast Data Transfers: With great speed comes great data transfers. Wi-Fi’s wide-range infrastructure supports hundreds of megabits per second, allowing huge amounts of data transfers.

Q31. What is an IoT platform?

IoT platform helps devices connect to a range of devices such as development boards, microprocessors, sensors, and so on. These platforms also act as a mediator to connect these devices to each other and to pass and receive information from these various devices while helping us in processing the incoming data, building logic rules, and taking vital decisions on the basis of incoming data.

Q32. What is IoT Thingworx?

Thingworx is a leading Industrial IoT platform that helps us connect to different edge devices for data analysis and data visualisation. It is also capable of being integrated with augmented reality to offer a thrilling experience to the end user.

Q33. What is IoT Salesforce?

Salesforce is essentially a business application that provides services to end-users or business users. It improves services with the help of big data obtained from connected devices. Salesforce has the capability to directly talk to the connected devices and start context-based alerts and actions.

Q34. What is IoT Contiki OS?

Contiki is a portable and open-source operating system that is specifically designed for IoT devices like wireless sensors, networking devices, and low-power microcontrollers.

Q35. List a few communication components of Contiki OS.

The communication components used by Contiki are uIP, uIPv6, Rime, 6LoWPAN (IPv6 over Low Power Wireless Personal Area Network), RPl, CoAp, and a few more.

Q36. What is GE Predix?

GE Predix is a cloud platform, which is a PaaS (Platform as a Service) that specifically targets IoT applications and performs data analytics on large amounts of data for further maintenance and operations.

Q37. What is M2M?

M2M is the abbreviation for Machine-to-Machine. It provides point-to-point exchanges of information without an internet connection and does not require any sort of manual human intervention.

Q38. What are the differences between IoT and M2M?

The differences between IoT and M2M are:

SL.NO	CRITERIA	IoT	M2M
1	Abbreviation	Internet of Things	Machine-to-Machine
2	Intelligence	Devices are capable of making their own decisions	M2M devices are intelligent only to a certain extent
3	Connection used	Network and other wireless communications	M2M devices use point-to-point communication
4	Protocols	TCP/IP protocols such as HTTP, HTTPS, FTP, and Telnet, etc	Traditional and less secure communication protocols are used
5	Data Sharing	In IoT devices data is shared between applications	Data is shared only between allowed connections
6	Internet	IoT devices need internet	M2M devices don’t need internet
7	Scope	Very bright scope	Limited scope
8	Scalability	Scalable	Not scalable

Q39. List a few features of M2M

M2M has a lot of features. Some of them are:

a. M2M devices consume lower power as compared to other technologies.
b. M2M acts as a network operator.
c. It provides packet-switched services.
d. It is capable of detecting events with the help of its monitoring abilities.
e. M2M allows for a delay while transferring data.
f. It lets the user specify a time to send and receive data.
g. M2M continuously receives and sends minimal amounts of data.
h. M2M sends an alert call to awaken the other devices when the device enters an unknown premise.

Q40. What is an IoT development board?

An IoT development board is a printed circuit board with circuitry and hardware designed to assist experiments with a specific microcontroller. It consists of a programming interface that lets you program the microcontroller from the desktop, power circuit, basic output buttons, basic input, and input/output pins that are used to connect sensors, motors, LCD screens, and more.

Q41. Explain IoT shodan in brief

Shodan is the abbreviation for Sentient Hyper-Optimized Data Access Network. Shodan is essentially an IoT search engine used for mapping and providing information about internet-connected devices.

Q42. What is a thermocouple sensor

A thermocouple sensor is a sensor that measures temperature by coupling two metal pieces together. When a voltage is generated by the metal conductors, the temperature is calculated. This sensor has the capability to measure a wide temperature range, thus making it suitable for various applications, such as scientific research, industrial settings, home appliances, etc.

Q43. What do you understand by the term Thingful?

Thingful, like Shodan, is a search engine for the Internet of Things that allows secure interoperability between millions of IoT objects via the Internet. Thingful is also used to control how data is used and empowers one to make more decisive and valuable decisions.

Q44. Explain interrupts in Arduino

In Arduino, interrupts enable specific tasks to process in the background and are enabled by default. The main role of interrupts is to ensure the device processor responds quickly to essential events.

Q45. Explain IoT testing in brief

As the name suggests, IoT testing is the process of testing to check IoT devices. Since there is an increasing need to deliver better and faster services, there is a huge demand to access, create, use, and share data from any device. Therefore, there is a need to provide greater insight and control over various interconnected IoT devices. This is why the IOT testing framework is crucial.

Q46. What is IGMP? Explain it in brief.

IGMP is the abbreviation for Internet Group Management Protocol. IGMP is a communication protocol used by hosts and adjacent routers for multicasting communication with Internet Protocol networks and uses the resources efficiently to transmit the data packets.

Q47. Explain the Zigbee protocol in brief.

Zigbee is a protocol that was designed for mesh networks. It is very suitable for home automation applications as it is one of the most used mesh protocols in IoT environments.

Q48. What do you understand by MQTT?

MQTT is the abbreviation for “Message Queuing Telemetry Transport”. MQTT uses a publish-subscribe architecture to enable machine-to-machine communication. MQTT is also used for connecting wireless networks with varying levels of latency stemming from bandwidth constraints or unreliable connections.

Q49. What does CARP stand for? Explain CARP in brief.

CARP stands for “Caching Array Routing Protocol”. It is a protocol developed by Microsoft and implemented in the Microsoft Proxy server that allows multiple proxy servers to array as a single logical cache for distributed content caching.

Q50. what are the different types of errors ICMP can handle?

ICMP has the capability to report the error messages to the sender. ICMP handles 5 types of errors, they are
1. Destination Unreachable
2. Source Quench
3. Time Exceeded
4. Parameter Problems
5. Redirection