IOT Interview Question and Answers

1. What is IoT? (Internet of Things)

Kevin Ashton created the phrase IoT (Internet of Things) in 1999. It is a worldwide network of interconnected physical objects (also known as "things") capable of collecting and exchanging data without the need for human interaction. These devices have embedded systems (software, electronics, networks, and sensors) that can collect data about the environment, send data across a network, respond to remote orders, and conduct actions based on the information gathered. Wearables, implants, vehicles, machinery, smartphones, appliances, computing systems, and any other item that can send and receive data are all examples of IoT devices or things available today.

Big data networks, cloud-based storage and computing, and Cyber-Physical Systems can all be integrated. the Internet of Things is largely concerned with extending internet connectivity from traditional devices (such as computers, mobile phones, and tablets) to relatively simple items such as toasters. It converts old "dumb" gadgets into "smart" devices by allowing them to send data over the internet, allowing them to communicate with people and other IoT-enabled devices. 

2. What are the various components of the Internet of Things?

The following are the four major components of IoT devices:

Sensors: A sensor or device is an essential component for collecting real-time data from the environment. This data can be of various types. This could be as simple as a temperature sensor, GPS, or accelerometer on your phone, or as complex as a social media platform's live video capability. Sensors allow IoT devices to communicate with the outside world and environment.

All data is transmitted to a cloud infrastructure once it is collected. This might be accomplished by connecting the sensors to the cloud through a variety of communication channels, including mobile or satellite networks, Bluetooth, WI-FI, WAN, and so on. Various IoT devices

Different types of connectivity are used by different devices.

Data Processing: Once the data has been collected and transferred to the cloud, the data processors are responsible for processing it. From regulating the temperature of the air conditioner to identifying faces on mobile phones, data processing software may improve IoT devices in a variety of ways.

User Interface: A User Interface is how an IoT device communicates with a user. A user interface is the visible and tactile part of an IoT system that users can interact with. It entails presenting data in a way that is beneficial to the end user. Users will be more likely to interact with a well-designed user interface because it will make their experience easier. The information must be made available to everyone. end-users in some way, for as giving them notifications via email or text message.

3. What are the benefits of the Internet of Things?

An Internet of Things (IoT) system is a sophisticated automation and analytics system that combines networking, big data, sensors, and artificial intelligence to deliver a comprehensive solution. It has the following advantages:
Improved client engagement: By automating tasks, IoT enables a better customer experience. Sensors in a car, for example, will detect any problem automatically. Both the driver and the manufacturer will be alerted.
Technology has been upgraded and made more efficient thanks to the Internet of Things. It has made even ancient "dumb" gadgets "smart" by allowing them to send data via the internet, allowing them to communicate with people and other IoT-enabled equipment. Coffee machines, smart toys, smart microwaves, and other smart devices are examples.

Accessibility: The Internet of Things has made it possible to obtain real-time data from practically everywhere. All you need is an internet-connected smart device.

Better Insights: We currently make judgments based on superficial data, but IoT gives real-time data that leads to more efficient resource management.
New business prospects: You may find new business insights and generate new possibilities while lowering operational expenses by collecting and analyzing data from the network.

Time management that works: Overall, the Internet of Things can help you save a significant amount of time. We may read the latest news on our phones, peruse a blog about our favorite activity, or shop online while commuting to work.
Strengthened security

measures: Access control solutions that use IoT can give additional security. to businesses and individuals For example, IoT technology in surveillance can help a business improve security standards and spot any questionable activities.

4. What are some of the IoT's problems or risks?

Some of the security threats linked with IoT include:

IoT devices that are connected are vulnerable to hackers. Many IoT devices capture and send personal data over an open network that hackers can easily access. Cloud endpoints can potentially be used by hackers to target servers.

In a fast-paced market like the Internet of Things, many companies and manufacturers rush to release their products and software without thoroughly testing them. Many of them also fail to deliver timely updates. IoT gadgets, unlike other devices such as smartphones, are not updated, making them vulnerable to data theft. As a result, IoT devices should be rigorously examined and updated as soon as new vulnerabilities are discovered. To preserve security, they must be identified.

People are unaware of the Internet of Things, despite it being a rapidly emerging technology. The user's lack of information and awareness of the capabilities of IoT is a serious security hazard. This is dangerous for all users.

Network Connectivity: Many IoT devices struggle with network connectivity. Especially if the devices are widely scattered, in remote places, or if bandwidth is scarce.

Because of the extremely scattered nature of IoT devices, ensuring the stability of IoT systems can be problematic. Natural disasters, disruptions in cloud services, power outages, and system failures can all influence the components that make up an IoT system.

5. What are the different types of sensors in the Internet of Things?

Internet-of-Thing sensors have gained popularity in recent years as a means of increasing production, cutting costs, and boosting worker safety. Sensors are devices that detect and respond to changes in the environment's conditions. They detect specific types of circumstances in the physical world (such as light, heat, sound, distance, pressure, presence or absence of gas/liquid, and so on) and generate a signal (typically an electrical signal) to indicate their magnitude. The following sensors are frequently used in IoT systems:

Sensors for temperature
Sensor of pressure
Sensors that detect movement
Gas detector
Sensor of proximity
Infrared sensors
Sensor for smoke, etc.

6. What are the layers of the Internet of Things protocol stack? Create an IoT protocol classification.

Protocols for the Internet of Things (IoT) protect data and ensure that it is safely shared between devices via the Internet. IoT protocols specify how data is sent over the internet. They maintain the security of data shared between linked IoT devices by doing so.

7. What are the various IoT communication models?

The Internet of Things is about linking things to the Internet in general, although how they connect isn't always clear. IoT devices use technical communication models to connect and communicate. A successful communication model explains how the process works and how to communicate effectively. The Internet of Things (IoT) makes it possible for

People and objects (devices) must be able to connect from anywhere, using any network or service.

Communication model types -

The client (IoT Device) makes requests, and the server responds to those requests in this communication architecture. The server selects what response to offer after receiving a request, then retrieves the requested data, prepares the response, and sends it back to the client. Because the data between requests is not stored, this approach is stateless, and each request is handled individually.

Publisher-Subscriber Model: This communication model includes publishers, brokers, and consumers. Publishers are data sources that transmit information to topics. Consumers (who consume data from subjects) subscribe to topics, which are managed by the broker.

Publishers and customers are completely oblivious of one another. When the broker receives data on a topic from the publisher, it distributes it to all subscribers. As a result, brokers are in charge of obtaining data from publishers and forwarding it to the correct consumers.

Push-Draw Communication Paradigm: In this communication model, data producers push data into queues, while data consumers pull data from the queues. Neither the manufacturer nor the consumer needs to be aware of one another. The queues aid in the decoupling of signals between consumers and producers. Queues also serve as a buffer when the rate at which producers push data differs from the rate at which consumers pull it.

Exclusive-Pair Model: Exclusive pairs are bidirectional, full-duplex communication models established for Client-server relationships that are continual or continuous. Clients and servers can exchange messages after establishing a connection. The connection remains open as long as the client does not send a request to disconnect it. Every open connection is visible to the server.

8. Create some of the most popular IoT apps.

The following are some of the most prevalent IoT applications in the real world:

Smart Houses: One of the most practical IoT applications is smart homes. Though IoT is used at various levels in smart homes, the greatest one combines intelligent systems with entertainment. Example: Set-top box with remote recording capability, automatic lighting system, smart lock, and so on.
Connected Health: Real-time monitoring and patient care are possible with connected health systems. Patient data helps doctors make better judgments. In addition, the Internet of Things improves the power, precision, and availability of present devices.
Wearables: One of the first sectors to use IoT at scale was the wearables industry. Today, a variety of wearable gadgets are available, including Fitbits, heart rate monitors, and smartwatches are all popular options.
Connected Automobiles: Connected cars employ onboard sensors and internet connectivity to improve their operation, maintenance, and passenger comfort. Tesla, BMW, Apple, and Google are among the main automakers working on the next revolution in the automobile business.

Hospitality: Using IoT in the hotel industry results in a higher level of service quality. Using electronic keys supplied directly to guests' mobile devices, several interactions can be automated. As a result of IoT technology, integrated applications can track visitors' positions, give offers or information about fun activities, place room service or room order orders, and automatically charge the room account.

Farming: A wide range of implements are used. Drip irrigation, crop patterns, water distribution, drones for farm surveillance, and other issues were addressed. These solutions will allow farmers to enhance yields while also addressing problems.

9. Describe the Internet of Things.

IoT devices are powered by artificial intelligence. Sensors, a cloud component, data processing software, and cutting-edge user interfaces are all part of the Internet of Things.

Sensors and gadgets are connected to the cloud via some sort of connectivity in IoT systems. A Raspberry Pi with a quadcore processor can be utilized as an IoT device's "Internet gateway." It's a card-sized computer with GIPO (general purpose input/output) pins for controlling outputs and sensors for collecting data about real-world circumstances. A sensor collects real-time data from the environment and sends it to the cloud infrastructure. The software may evaluate the data once it reaches the cloud and decides what action to take, such as forwarding it. 

10. What does BLE (Bluetooth Low Energy) stand for?

BLE (Bluetooth Low Energy) is a sort of Bluetooth that requires less power and energy, according to beginners. BLE, or Bluetooth Smart, is a relatively new kind of Bluetooth technology that uses significantly less power and expenses while providing a comparable range of communication. BLE is not a substitute for Classic Bluetooth, as seen in the diagram, and they both serve a specific market. The Bluetooth Low Energy technology was created to help with the Internet of Things. In general, the Internet of Things is connecting objects, usually over a wireless connection such as Bluetooth low energy, so that they may communicate and share data. It has BLE has become a favored and optimal alternative for IoT because of its excellent energy economy. Bluetooth LE is increasingly being used by IoT enthusiasts and application developers to link smart devices.

11. What is the purpose of a thermocouple sensor?

A thermocouple is a temperature sensor that uses two metal parts to monitor the temperature. The temperature is taken at the intersection of these two metal pieces, which are linked at one end. The metal conductors provide a modest voltage that can be used to calculate the temperature. A thermocouple is a basic, reliable, and inexpensive temperature sensor that comes in a variety of shapes and sizes. They also have a wide temperature range, making them useful for a wide range of applications, including scientific research, industrial settings, and home appliances.

12. Define the phrase "smart city" in the context of IoT.

Since its beginnings, IoT technology has been a driving factor behind the development of smart cities. The Internet of Things (IoT) will As more countries adopt next-generation connectivity, the influence on our lives will expand. Smart cities use IoT devices like connected sensors, lights, and meters to collect and analyze data. Cities use this information to improve infrastructure, utilities, and other civic services as a result. 

The Internet of Things can be used to develop intelligent energy grids, automated waste management systems, smart homes, enhanced security systems, traffic control mechanisms, water conservation mechanisms, smart lighting, and more. IoT has given public utilities and urban planning a new layer of artificial intelligence and creativity, allowing them to be more intuitive. Smart houses and cities have resulted from these advancements.

13. What does PWM (Pulse Width Modulation) mean?

Have difficulties controlling the brightness of your project's LEDs? Changing the power supply voltage directly in the circuit is difficult. In that case, you can use Pulse Width Modulation (PWM).

Pulse Width Modulation (PWM), also referred to as PDM (Pulse Duration Modulation) refers to modulating the quantity of power given to a device PWM is an efficient way to manage the amount of energy given to a load without wasting any energy. It is a technique for creating an analog signal from a digital source. PWM is a voltage regulator that is used to adjust brightness in Smart Lighting Systems as well as motor speed. 

14. Describe Shodan.

Shodan (Sentient Hyper-Optimized Data Access Network) is a search engine comparable to Google that searches for maps and information about internet-connected devices and systems rather than websites. Shodan is also known as an Internet of Things search engine. Shodan, to put it simply, is an Internet-connected device identification tool. It maintains track of all machines having a direct connection to the Internet.

Shodan is a technology used by cybersecurity specialists to defend individuals, businesses, and even public utilities against cyber-attacks. Shodan allows you to search for any internet-connected device and determine whether it is publicly accessible.

15. What do you mean by Internet of Things, Contiki?

Contiki is an operating system designed for Internet of Things (IoT) devices with limited memory, power, and bandwidth. and computing power Despite its simplicity, it has many of the features that current operating systems have. It can help manage programs, processes, resources, memory, and communication. It has been a go-to operating system for many academics, researchers, and professionals due to its lightweight (by modern standards), mature, and adaptable character.

16. Identify some of the best databases for IoT.

The databases listed below are suitable for IoT:

InfluxDB
Apache Cassandra
RethinkDB
MongoDB\sSqlite\s

17. Explanation about sharding

Sharding is the process of breaking down very large databases into smaller, quicker, and easier-to-manage data shards. A shard is a small slice of data from a larger data source. Sharding is the process of splitting a logical dataset into numerous databases to store it more effectively. Sharding is required when a dataset is too large to fit into a single database.

18. What exactly do you mean when you say replication?

Data is synced between two or more servers in replication. This is a technique for storing the same data on several devices. a single website or server This feature allows data to be accessed without interruption even when the server is down or there is a lot of traffic. Users have consistent access to data without interfering with or slowing down other users' access.

Data replication is much more than a backup. A publisher is a server that generates the data, and a subscriber is a server where it is duplicated. The publisher synchronizes its transaction with the subscriber and updates subscriber data automatically using data replication. A change made by the publisher is automatically reflected in the subscriber's account.

19. Explain the distinction between IoT and M2M.

Internet of Things (IoT): It's a network made up of interconnected physical items that can collect and exchange data. These devices have embedded systems (software, electronics, networks, and sensors) that can collect data about the environment, communicate data across a network, respond to remote orders, and conduct actions based on the information gathered. M2M (Machine to Machine) technology includes the Internet of Things (IoT). M2M is when two machines communicate without the need for human involvement.

M2M (Machine to Machine): In M2M, devices communicate directly with one another over wired or wireless channels without the need for human intervention. It allows devices to communicate and exchange information. without using the internet to communicate with one another M2M communications can be used for a variety of purposes, including security, tracking and tracing, manufacturing, and facility management.

20. What exactly is an IoT Gateway? What is the function of a gateway in the Internet of Things?

IoT gateways, for example, allow IoT devices, sensors, equipment, and systems to communicate with one another. An IoT gateway is essentially a central hub for all IoT devices. It links IoT devices to one other and the cloud, transforming device communication and analyzing data to provide usable information. An IoT gateway performs several key activities, including interpreting protocols, encrypting, processing, managing, and filtering data. Gateways are used to connect devices and sensors to the cloud as part of an IoT ecosystem.
The following are some of the most prevalent uses for IoT gateways:

Devices that connect
Using the cloud to connect devices
IoT communication transformation
Filtering data
lowering safety risks, etc.