IoT Interview Questions and Answers for 2025

The notion of a "smart city" aims to improve urban areas throughout the nation. These cities are technologically advanced and rely on electronic technologies for resource management and communication. The information gathered by these gadgets is used to identify problem areas, which may then be remedied using scientific approaches to make city life run more smoothly. Using IoT devices efficiently and optimising data effectively, the IoT may improve urban living conditions. 

Intuitive features of IoT devices and increased network participation allow IoT to foster adaptability, transparency, and efficiency in infrastructure design. Energy-saving initiatives also find support in the IoT. Since IoT offers so many benefits, it is feasible for governments to pursue the goal of creating smart cities all over the world. 

Smart energy grids, automated waste management systems, smart houses, enhanced security systems, improved traffic control mechanisms, expanded security features, water conservation mechanisms, and much more are all conceivable thanks to the Internet of Things. IoT, which benefits from both AI and new technological developments, has made intuitive public services and city planning possible. Due to this, "smart" houses and urban areas have emerged.

An embedded system is a mix of hardware, software, and firmware that has been customised for a particular application. It is a tiny computer that may be incorporated in mechanical or electrical systems, such as autos, industrial equipment, medical devices, smart speakers, or digital watches. Examples of these kinds of systems include Programmability or functionality lockdown may be characteristics of an embedded system. 

In most cases, it consists of a CPU, memory, power supply, and communication ports, and it also contains the software that is required to carry out activities. In addition, certain embedded devices may run a lightweight operating system, such as a Linux distribution with less features. 

When data must be sent from the processor of an embedded system to a peripheral device—which may be a gateway, a central data processing platform, or even another embedded system—the embedded system makes use of communication ports. It is possible that the processor is a microprocessor, but it might also be a microcontroller, which is like a microprocessor but also has integrated memory and peripheral ports.  

The processor makes use of specialised software that is stored in memory to understand the data that it has acquired. IoT devices may have embedded systems that vastly differ from one another in terms of complexity and function; nonetheless, they all have the ability to process and send data. 

Any one of the following categories of hardware components may be included into an embedded system: 

• Sensor or Any Other Kind of Input Device: Information is gathered from the world that may be seen and then converted into an electrical signal. The input device has an effect on the kinds of data that are collected. 
• Analog-to-digital Converter: Transforms an electrical signal from its analogue form into its digital equivalent. 
• Processor: Performs operations on the digital data that was collected by the sensor or other input device. 
• Memory: Contains specialised software as well as the digital data that was gathered from the sensor or other input device. 
• Digital-to-analog Converter: Performs a conversion from the digital data produced by the CPU to the analogue data. 
• ActuatoR: Performs an action in accordance with the information obtained from a sensor or other input device. 

It is possible that an embedded system will include more than one sensor and actuator. For instance, a system may consist of a number of sensors that are responsible for collecting data on the surrounding environment. This data is then transformed before being transferred to the processor.  

After being processed, the data is then translated once again and transmitted on to a number of actuators, which carry out the activities that have been prescribed. 

One definition of a sensor describes it as "a physical item that detects and reacts to input from its surrounding environment." For instance, a sensor that registers the temperatures that are present inside a piece of heavy equipment only detects and reacts to the temperatures that are present within that machinery, as opposed to detecting the temperatures that are present outside of the gear.  

Typically, the information that is gathered by a sensor is then electronically communicated to other components that are a part of an embedded system, where it is then transformed and processed as required. The Internet of Things industry provides support for a wide variety of sensor types, some of which include sensors that may monitor light, heat, motion, moisture, temperature, pressure, proximity, smoke, chemicals, air quality, or other environmental factors. Some Internet of Things devices have many sensors built into them so that they may collect a variety of data.  

For instance, a thermostat in an office building may be equipped with the capability to monitor both the temperature and motion. If there is no one in the room, the thermostat will automatically adjust itself to a lower temperature. 

A sensor is not the same thing as an actuator, which is anything that reacts to the data that the sensor produces. 

A wide variety of sensors, such as the following, are available for use in agriculture: 

Airflow is a measurement of the air permeability of the soil. 

• Acoustic: Determines the decibel level of the sounds made by pests. 
• Chemical: Determines the concentration of a certain chemical, such as ammonium, potassium, or nitrate, or determines the circumstances present, such as the pH level or the existence of a particular ion. 
• Electromagnetic: The capacity of the soil to conduct electrical charge is measured, and this measurement may be used to identify features like as the amount of water present, the amount of organic matter, or the degree to which the soil is saturated. 
• Electrochemical: Determines the levels of nutrients present in the soil. 
• Humidity: Determines the amount of moisture present in the air, for example in a greenhouse. 
• Soil Moisture: Determines the level of moisture present in the soil. 

An Internet of Things gateway may be a physical device or a software application. Its purpose is to permit connections between Internet of Things devices and the network that transmits data from the devices to a centralised platform, such as the public cloud, where the data is processed and stored. Smart device gateways and cloud endpoint protection products have the ability to move data in both directions while also assisting in the prevention of data from being compromised.  

These products frequently employ strategies such as tamper detection, encryption, crypto engines, or hardware random number generators. Gateways may also incorporate characteristics that assist Internet of Things communications, such as caching, buffering, filtering, data purification, or even data aggregation. These features might be included in a gateway. 

Bluetooth, also known as Bluetooth Classic on occasion, is often put to use for reasons that are dissimilar to those served by Bluetooth Low Energy. Bluetooth Classic is capable of handling far more data, but at the expense of significantly increased battery consumption.

Bluetooth Low Energy uses far less power than its predecessor, but it cannot transfer nearly as much data. The table that follows gives an overview of some of the distinctions that exist between the two types of technology. 

Internet Protocol Version 6, often known as IPv6, is an improvement over IPv4. One of the most notable changes is that IPv6 expands IP address sizes from 32 bits to 128 bits. IPv4 can only hold around 4.2 billion addresses due to its 32-bit restriction, which has already proven inadequate. Because of the growing number of IoT devices and other platforms that employ IP addresses, a system that can manage future addressing requirements is required.  

IPv6 was intended by the industry to support billions of devices, making it ideal for IoT. IPv6 also offers enhanced security and connection. However, it is the extra IP addresses that take centre stage, which is why many feel that IPv6 will be critical to the future development of IoT. 

Zigbee Alliance is a consortium of companies committed to open standards for Internet of Things infrastructure and gadgets. It is a certification programme that helps make sure devices are compatible with one another and adhere to international standards for wireless Internet of Things (IoT) connection. Zigbee, an open standard for constructing low-power, self-organizing mesh networks, is one of its most well-known achievements.

Interoperability problems are minimized since all Zigbee-certified devices speak the same IoT language when connecting and communicating with one another. Zigbee is built on top of the IEEE 802.15 standard and adds a network layer, security features, and an application framework. 

The following use cases are examples of the ways in which enterprises might profit from IoT data analytics: 

• Predicting the needs and wants of the client base in order to more effectively plan product features and release cycles, as well as provide innovative value-added services. 
• Optimizing the heating, ventilation, and air conditioning (HVAC) systems in enclosed spaces such as office buildings, retail malls, medical facilities, and data centres. 
• Increasing the quality of treatment that is provided to patients who have illnesses that are quite similar to one another while also being able to better comprehend those problems and focus on the requirements of particular people. 
• Maximizing the efficiency of delivery operations such as scheduling, navigating, and maintaining vehicles, while also cutting down on fuel costs and emissions. 
• Gaining an in-depth understanding of the ways in which customers utilise their goods in order for a corporation to design marketing campaigns with a greater focus on strategy. 
• Detecting and locating possible risks to data security in order to improve data protection and ensure compliance with regulatory mandates. 
• Enhancing agricultural methods to generate more plentiful but sustainable yields; optimizing industrial processes to make greater use of equipment and enhance workflows; analyzing how utilities are provided to clients across areas and gaining a better knowledge of their consumption patterns.

Edge computing can be beneficial to the Internet of Things in a number of ways, including the following: 

• It can support IoT devices in environments with limited network connectivity, such as agricultural settings, offshore oil rigs, or other remote locations. 
• It can reduce network congestion by pre-processing data in an edge environment and then transmitting only the aggregated data to a central repository; and it can support IoT devices in environments where there is no network connectivity at all. 
• Reducing potential security and compliance risks by transmitting less data across the internet or by creating smaller network segments that are easier to manage and troubleshoot. 
• Reducing latency by processing the data closer to IoT devices that are generating that data, resulting in quicker response times. 
• Decentralizing massive cloud centres to better serve specific environments and reduce the costs and complexities that come with transmitting, managing, storing, and producing data. 

One of the most frequently posed IoT testing interview questions, be ready for it. The impending proliferation of 5G networks may have several different effects on the Internet of Things (IoT): 

• Supporting more sophisticated use cases is made feasible by having a higher bandwidth and faster throughputs. This is particularly true for use cases that need shorter reaction times, such as automated public transit or traffic control systems. 
• Because organizations have the ability to disperse more sensors, they can collect a wider range of information about environmental factors or the behaviour of equipment. This leads to more comprehensive analytics and a greater capacity to automate operations on both the industrial and consumer levels. 
• The Internet of Things might be enabled on a more extensive scale in regions where it would otherwise be impossible to accomplish with the aid of 5G, which would be beneficial to businesses like as agriculture and healthcare. 
• Establishing smart cities, which call for a greater saturation of Internet of Things devices, is made simpler by the quicker throughput and the capacity to handle data from a greater number of sensors. 
• 5G might help manufacturers improve their inventory tracking throughout the product's lifespan, as well as improve their ability to govern processes and optimise operations. 
• 5G makes it possible for businesses and governments to react to a wider variety of catastrophes, including medical emergencies, pipeline breaches, fires, traffic accidents, weather events, and natural disasters, in a more prompt and effective manner. 
• 5G has the potential to improve automobiles in a number of ways, including making them safer, easier to maintain, and more economical with fuel, while also bringing the concept of driverless vehicles closer to becoming a reality. 

An enterprise can safeguard its Internet of Things systems by taking a number of procedures, including the following: 

• Integrate security from the beginning of the design process and make security the default setting. 
• To protect the devices that make up the internet of things, implement public key infrastructures and use 509 digital certificates. 
• Use application performance indicators to preserve data integrity. 
• Endpoint hardening should be implemented, such as making devices tamper-proof or tamper-evident, and it should also be ensured that each device has a unique identity. 
• Employ sophisticated cryptographic techniques in order to encrypt data both while it is in transit and while it is stored. 
• Protect networks by turning off port forwarding, shutting ports that are not being used, banning IP addresses that are not allowed, and ensuring that all network software and equipment is up to date. In addition, instal antimalware, firewalls, intrusion detection systems, intrusion prevention systems, and any other protective measures that may be required. 
• Identify and take inventory of IoT devices connected to the network by using the methods for controlling network access. 
• Utilize distinct networks for Internet of Things (IoT) devices that connect directly to the web. 
• Employ security gateways so that they may act as go-betweens for the Internet of Things devices and the network. 
• Always be sure to instal the latest updates and patches for any software that is a part of the Internet of Things system or that is used to manage IoT components. 
• It is important to provide anyone who engage on the Internet of Things system in any capacity, whether they are planning, implementing, creating, or managing, with security training and instruction. 

The internet of everything (IoE) is a radical new idea that expands the scope of connection beyond the Internet of Things (IoT) and its emphasis on physical objects to also include digital ones such as people, processes, and data.

That "advantage of IoE is derived from the cumulative effect of linking people, process, data, and things, and the value this greater connectivity produces as 'everything' comes online," was Cisco's original explanation for the notion of IoE.

When compared to IoE, which also includes connections between humans and machines, IoT solely refers to the networking of physical items. Cisco and other advocates of IoE think that by "connecting the disconnected," new value may be created for those who take advantage of it.

Businesses that are deploying an IoT system should perform several different forms of testing, including the ones that are listed below:

• Ensures that an Internet of Things device provides the best possible user experience (UX), taking into account the context in which the device would normally be utilised.
• Functionality ensures that all of the functionalities on the Internet of Things device function as intended.
• Ensures that all relevant security requirements and regulatory standards are met by IoT devices, software, and infrastructure (including network, compute, and storage).
• Integrity of the data maintains the data's authenticity throughout all communication channels, during all processing procedures, and inside all storage systems.
• Performance ensures that devices, software, and infrastructure associated with the Internet of Things achieve the level of performance required to offer uninterrupted services within the allotted amount of time.
• Scalability ensures that the Internet of Things system can grow as required to meet changing needs without compromising performance or causing disruptions to existing services.
• Reliability ensures that the Internet of Things devices and systems can provide the number of services that are anticipated without experiencing any downtimes that are unnecessarily lengthy or drawn out.
• Connection ensures that Internet of Things devices and system components may correctly interact with one another without interruptions in connectivity or data transfer activities and can immediately recover from any disruptions without suffering any loss of data.
• Compatibility ensures that compatibility concerns between Internet of Things devices and other components of the system are recognised and resolved, and that devices may be added, relocated, or withdrawn without causing any interruptions to the services being provided.
• Testing that is exploratory ensures that the Internet of Things system functions as intended under real-world situations, while also uncovering flaws that other methods of testing could miss.

An open-source platform known as Arduino may be used to construct electrical projects with the help of user-friendly hardware and software. Each and every Arduino board has a microcontroller as its signature component. On-board microcontrollers have the ability to receive inputs (such as light falling on a sensor or an item being in close proximity to a sensor) and convert them into outputs (drive a motor, ring an alarm, turn on an LED, display information on an LCD).

Connecting numerous devices and facilitating the simultaneous flow of data between them is a possibility. You may also monitor them remotely using a simple user interface, which is a possibility.

Raspberry Pi is a credit-card-sized computer having GPIO (General Purpose Input Output) ports, WiFi, and Bluetooth that enable it to interact with, control, and connect to other devices. Combining IoT applications with Raspberry Pi facilitates organisations' adoption of technology.

A programme is known as a sketch while working with Arduino. In other words, it is a piece of code that is uploaded into an Arduino board in order for it to be run on that board. It is feasible to minimise the file size of the sketch by eliminating unused libraries from the code and keeping it as straightforward and concise as possible.

What exactly is meant by the abbreviation GPIO (General Purpose Input/Output)? 

GPIO, which stands for "General-purpose input/output," is a standard interface that allows microcontrollers like the Raspberry Pi to connect to electrical components or devices that are external to the system.

These are programmable pins on an integrated circuit or board that allow for the control of digital input or output signals by programming. These pins may be found on an integrated circuit or board. 

WSN (Wireless sensor network): It utilises a network of specialised sensors to monitor and record the physical conditions of the environment and arrange the collected data centrally. WSN: Sensor nodes linked wirelessly to collect data. 

The Internet of Things (IoT) is a network of networked, data-collecting and -exchanging physical items.

These devices feature embedded systems (software, electronics, networks, and sensors) that may gather data about their surroundings, communicate data across a network, react to remote orders, or take action depending on the data acquired. IoT: WSN + Any physical thing (Thing) + Internet + App + Cloud computing + etc. 

Predix, a software platform developed by General Electric (GE), is used to gather data from various industrial instruments. Using a PaaS that is hosted in the cloud, this platform provides industrial-grade analytics for the purpose of operations optimization and performance management (platform as a service).

There are many wearable Arduino boards available, including the ones listed below:

• Lilypad Arduino main board
• Lilypad Arduino simple
• Lilypad Arduino simple snap
• Lilypad Arduino USB

The process of monitoring a specific object and its position is referred to as "asset tracking." An asset may be anything from a hammer to an X-ray equipment, a car to a shipping box, or even a person. Where does the Internet of Things come into play? IoT tracking systems employ sensors and asset management software to automatically monitor objects, as opposed to manually tracking assets, such as a supervisor filling out a form when the item arrives at a certain area.

The property is outfitted with sensors that broadcast their position over the internet either continuously or at regular intervals, and the programme presents this information to you for viewing. Various forms of Internet of Things asset tracking systems each have their own unique method of transmitting location information, such as via the use of GPS, Wi-Fi, or cellular networks.

There is a search engine dedicated to the internet of things called Thingful (IoT). It offers a geographical index of real-time data from connected devices located all over the world by making use of millions of IoT data resources that are freely accessible to the public. IoT administrators are able to recognise patterns, identify abnormalities, and evaluate trends with the help of Thingful so that they can address issues.

SSH may be used to control a Raspberry Pi that is operating in headless mode. The most recent version of the operating system has a built-in VNC server that may be used to access the remote desktop of a Raspberry Pi.

The following is a list of the many kinds of antennas that may be found in IoT devices: 

• Wire Antenna 
• PCB Antenna 
• Chip Antenna 
• Whip Antenna 
• Proprietary Antenna

To put it as plainly as possible, we are going to have to lay off workers because computers are going to be able to do many of the tasks that now need human diligence and precision. On the other hand, on the positive side, people receive the opportunity to master new skills so that they may control the machines and create their own area.

This has always been the rule of nature; although there is something we can do right now to lighten the load, in the next few weeks or days, we will be faced with an entirely new challenge. Therefore, I view this as an upbeat approach to coping with the challenges that we face on a daily basis.

The majority of vehicles on the road today are likely to be fitted with a global positioning system (GPS) and an advanced driver assistance system (ADAS), both of which collect data from the vehicle, process it so that it can be interpreted in the appropriate context, and then make decisions based on that data. For instance, the capacity to apply emergency brakes depending on the data collected by the sensors; the provision of assistance to the driver when parking the vehicle; and the provision of assistance to the driver while he is doing these actions.

All of these applications have made a significant improvement in terms of the ways in which the internet of things can assist an individual as well as businesses in conducting research and development to improve the one-of-a-kind offerings they make to customers in order to attract those customers to their businesses. 

When discussing the installation of the Internet of Things, the term "Thing" takes on a more relevant connotation since it takes into account the concept of something. 

For instance, a "thing" may be a shipping container that has an RFID tag and is transported from one site to another, during which time it provides the most up-to-date information anytime the RFID tag is scanned by an RFID reader. This "thing" is an example of an RFID-enabled "thing."

Another example of this would be a microchip that is included into your mobile phone or a fitness band that continually detects your physical motions and then transmits this data to a centralised database over the internet. 

There is a possibility that an active internet connection is not required for a sensor business, and the company may still function without it. 

When it comes to the Internet of Things, however, there is a control side that is linked with it.

This control side is required in order to monitor and share the information that is sent from the sensor to the central unit inside an active network.

This is the primary distinction that can be made between the internet of things and the companies that deal with sensors.