50 Multiple Choice Questions (MCQ) about IoT (Internet of Things) with Answers

Understanding IoT: Benefits, Features, Ecosystem, Applications, Sensors, and MCQs

IoT, short for Internet of Things, is a technology that allows everyday objects to be connected to the internet, enabling collection and exchange of data. This technology is transforming the way we live our lives by providing several benefits such as efficient resource utilization, time-saving, minimization of human effort, improved security, and development of AI.

Benefits of IoT:

  • Efficient resource utilization
  • Time-saving
  • Minimization of human effort
  • Improved security
  • Development of Artificial Intelligence

Features of IoT:

  • Connectivity of various things to the IoT platform
  • Data analysis used to build business intelligence
  • Integration of models to improve user experience

IoT Ecosystem:

IoT ecosystem comprises three layers:

  • The Perception Layer: Sensors sense and gather information about the environment such as temperature, humidity, sound, etc.
  • The Network Layer: Responsible for connecting smart things and transmitting data to servers
  • The Application Layer: Responsible for delivering application-specific services to the user

Applications of IoT:

  • Energy conservation
  • Smart transport
  • Social life and entertainment
  • Supply chain and logistics
  • Health and fitness
  • Smart environment
  • Home automation
  • Smart agriculture

IOT sensors:

IOT sensors are controllers that sense and capture real-world data, converting it to electrical signals and transmitting it to the cloud-based central server directly or through microcontrollers. Common types of sensors include temperature, humidity, proximity, level, and gyroscope sensors

Features of sensors include:

  • Range
  • Accuracy
  • Sensitivity
  • Resolution


Multiple Choice Questions on IoT

Exploring the Role of Cloud in Smart Grid Architecture

The role of cloud computing in smart grid architecture is mainly to manage the enormous amount of data generated by various sources. Cloud technology enables the integration of diverse data sources and provides real-time insights into the energy usage patterns.

The cloud helps in storing and processing vast amounts of data from various IoT devices, sensors, and smart meters. It enables scalability and flexibility to manage the peaks and troughs of data influx, which is essential for efficient grid operations. Additionally, cloud technology provides robust security measures such as authentication, encryption, and access controls, ensuring that the data is secure and protected from cyber-attacks.

Overall, cloud computing has a critical role to play in the smart grid architecture as it enables the optimization of energy distribution, improves grid reliability, and fosters sustainable energy usage.

// Example code snippet for accessing cloud-based data

Open IoT Sensor Deployment Management

Open IoT manages sensor registration and deployment through X-GSN network.

Identifying Java Extension File in IoT

In the context of Internet of Things (IoT), the Java extension file would be .jar. The .jar file is used for packaging and distributing Java-based applications and libraries. Other file extensions mentioned in the options are used for different purposes and technologies. .c is a file extension used for C programming language source files, .py is used for Python programming language files, and .exe is used for Windows executable files.

Total Voice Communication Types in IoT

In an IoT environment, there are three types of voice communication available, which are typically used to facilitate machine-to-machine (M2M) communication. These types are:

  1. Commands and Queries:
  2. This voice communication type is used to send commands from IoT devices to the cloud or other IoT devices, and to request information or perform queries.

  3. Notifications:
  4. Notifications are used to alert IoT devices or users of important information or events, such as sensor readings or system warnings.

  5. Streaming Audio:
  6. This type enables devices to transmit and receive live audio streams. Applications for streaming audio in IoT environments may include security or surveillance systems, or remote monitoring of machinery or equipment.

Note that other types of communication may also be used in IoT environments, such as text-based messaging or machine-to-human voice communication, but these are not considered voice communications specifically.

Standard Length of MAC Address

In networking, a MAC (Media Access Control) address is a unique identifier assigned to every network interface controller (NIC) for communicating on a network. The standard length of a MAC address is 48 bits.

Therefore, the correct answer is 48 bits (B).

What Does VNC Stand For?

In computing, VNC stands for Virtual Network Computing. It is a graphical desktop sharing system that allows remote access and control of a computer over a network connection. VNC works on a client-server model where the user can access and control a remote computer by installing a VNC client software on their own computer and connecting to a VNC server software running on the remote computer.

Language Preferred for IoT Analytics

Python is the preferred language for IoT analytics due to its versatility in handling data and its ease of use for complex analytical tasks. It allows for quick prototyping and has a robust set of data analysis libraries such as NumPy, Pandas, and Scipy. Additionally, Python's machine learning frameworks like TensorFlow and Keras make it ideal for developing predictive models using data from IoT devices. Therefore, Python offers an excellent solution for the data analysis requirements of an IoT system.

Identifying the Operator of the Core Element in Various Services

In which type of service does an IoT service provider operate the core element?

- PaaS - IaaS - SaaS - IoT service provider

Answer: The IoT service provider operates the core element in its service.

Explanation: In the given options, the operator of the core element is the IoT service provider. In general, PaaS is operated by a cloud service provider, IaaS by a cloud infrastructure provider, and SaaS by a software provider. However, in the case of IoT service, the service provider operates the core element, which may include devices, sensors, software, and cloud services that enable the IoT solution.

Identifying Incorrect Advantage of IoT

We need to identify the incorrect advantage of IoT among the given options:

Reduce waste
Enhanced data collection
Improve customer engagement

Answer: D) Security is not an advantage of IoT.

IoT Term Coined by Kevin Ashton

Kevin Ashton, a British technology pioneer, coined the term "Internet of Things" (IoT) in 1999. He used the term to describe how physical objects could be connected to the internet and communicate with other devices without human intervention.

Ashton's vision has become a reality today, and IoT is revolutionizing industries, including healthcare, transportation, and manufacturing.

Understanding Services in SOA

Business service is the correct term used in SOA for a service. It is designed to provide a specific and well-defined business functionality, which can be accessed by different applications or components.

Services in SOA are not limited to network or software services, but also include developer services that support the enterprise in building and deploying services. However, the primary focus is on the business services that fulfill the needs of the enterprise.

It is important to understand the term business service in SOA, as it plays a crucial role in achieving the service-oriented architecture's benefits and goals.

Therefore, the correct answer is C) Business service.


Using an API allows for system service portability, meaning that services can be easily moved between different systems because the API provides a standardized way for them to communicate with each other. The other options, such as device and network, are not as relevant to API usage in this context.

Identifying Security Concerns

One of the challenges in securing information is presence detection.

// Here is an example of implementing presence detection in a secure system

var authorizedUsers = ["Alice", "Bob", "Charlie"]; // List of authorized users
var currentUser = getUser(); // Get current user

if (authorizedUsers.includes(currentUser)) {
  accessGranted(); // Grant access to authorized users
} else {
  alert("Unauthorized access detected!"); // Alert on unauthorized access attempts
  logAccessAttempt(currentUser); // Log access attempts for later review

This code checks if the current user is included in the list of authorized users before granting access. If the user is unauthorized, an alert is triggered and the access attempt is logged for review. Implementing measures like this can help in securing sensitive information.

What Does SBC Stand for?

The full form of SBC is Smart Business Center.

It's important to note that SBC is an acronym, not an API.

Total Types of IoT Platforms

The IoT platform is divided into four types.

// Sample code to demonstrate the four types of IoT platforms

public class IoTPlatform {
    public static void main(String[] args) {
        String type1 = "Device management platforms";
        String type2 = "Connectivity management platforms";
        String type3 = "Cloud platforms";
        String type4 = "Business/IoT application enablement platforms";

        System.out.println("The four types of IoT platforms are:");
        System.out.println("1. " + type1);
        System.out.println("2. " + type2);
        System.out.println("3. " + type3);
        System.out.println("4. " + type4);

What does ITS stand for?

ITS stands for Intelligent Transportation Services.

This term refers to the advanced applications and technologies used in transportation to improve efficiency, safety, and sustainability. ITS includes various systems, such as intelligent traffic management, electronic toll collection, and advanced traveler information systems.

Monitoring an Application using Endpoints

In order to monitor an application, we can make use of endpoints. Endpoints provide us with various details about the application such as health, status, configuration, environment, etc.

Out of the given options, the correct answer would be endpoints, as they allow us to monitor the application.

Expressing Resolution in Terms of Bits

Resolution is typically expressed in terms of bits.

  int resolution = 1920; // Resolution of 1920x1080
  int bitsPerPixel = 24; // Typically 24 bits per pixel for high color depth
  int totalBits = resolution * resolution * bitsPerPixel; // Total number of bits required for the display

In the code sample above, the resolution is expressed in terms of pixels, but it can be easily converted to bits by multiplying it with the bits per pixel value.

Understanding SLA

SLA stands for Service Level Agreement. It is a contract between a service provider and a customer that defines the level of service that the customer expects from the provider. The SLA includes details such as the scope of service, performance metrics, and remedies if the service provider fails to meet the agreed-upon service levels.

Last Step of Reliable Data Transfer

In reliable data transfer, the last step is selective recovery, which ensures that any lost messages during transmission are identified and retransmitted to the receiver. This step is crucial in maintaining the integrity and completeness of the data being transferred. Other steps in reliable data transfer may include message acknowledgement, error correction, and flow control. By implementing these techniques, data can be transmitted efficiently and accurately, without the risk of data loss or corruption.

What is IoT?

IoT stands for Internet of Things.

The Internet of Things (IoT) refers to the concept of connecting internet-enabled devices that are embedded in everyday objects to the internet and to each other, allowing them to send and receive data. This can include anything from smart home appliances to vehicles to industrial machinery.

Year of Coining IoT Term

The term IoT was coined in 1999

// No code provided as it is a simple factual answer

Identifying IoT Platforms

Out of the following options, the correct answer is D) Flipkart, which is not an IoT platform. The other options are:

  1. Salesforce
  2. AWS
  3. Microsoft Azure

These are all examples of IoT platforms that offer various services and tools for building and managing IoT devices and applications.

What is IIoT?

IIoT stands for Industrial Internet of Things.

It refers to the application of internet of things (IoT) technologies in industries, such as manufacturing, transportation, and energy, to improve operational efficiency and productivity. The use of IIoT devices allows for the collection and analysis of data in real-time, enabling businesses to make better decisions and optimize their operations.

Examples of IIoT devices include sensors, smart meters, and industrial robots.


Identifying Non-Fundamental IoT System Components

Out of the given options, the non-fundamental component of an IoT system is transformers.

The other fundamental components of an IoT system are:

  • User interface
  • Sensors
  • Connectivity and data processing

These components work together in an IoT system to gather data from the environment, process it, and present it to users in a meaningful way.

Identifying the Layer Used for Wireless Connection in IoT Devices

In IoT devices, wireless connections are established through the data link layer. It is responsible for providing a reliable point-to-point or broadcast communication link between two or more devices.

// Example code for establishing a wireless connection in IoT devices using data link layer
void establishWirelessConnection(){
   // Code for initializing the wireless connection through the data link layer
   // Code for pairing the devices
   // Code for setting up the communication link

Open IoT Architecture Elements

The Open IoT Architecture consists of 7 elements:

  1. Device
  2. Secure Device Communication
  3. Gateway
  4. Cloud
  5. Service
  6. Application
  7. Business

Therefore, the correct answer is C) 7.


An IoT gateway is a device that bridges the communication gap between IoT devices, sensors, and the cloud. It is responsible for providing various functionalities like protocol abstraction, security with hardware, and data storage. However, among the given options, the most important functionality that an IoT gateway must provide is protocol abstraction, as it is essential in ensuring that diverse IoT devices with various protocols can communicate and work together. Therefore, option A is the correct answer.

Identifying IoT Device Protocol

To link all devices in IoT, the protocol used is TCP/IP. This protocol is essential for the communication and exchange of data between the various devices in an IoT network.

UDP is a different protocol used for establishing connections between devices, but it's not suitable for IoT systems. HTTP is also not used as a device protocol in IoT, but as a communication protocol between devices and servers.

Thus, TCP/IP is the standard protocol in IoT that ensures seamless and secure communication between devices.

// Example code using TCP/IP to connect IoT devices
// Create a server socket and bind it to a specific port
ServerSocket serverSocket = new ServerSocket(8080);

// Wait for incoming client connections
Socket clientSocket = serverSocket.accept();

// Read data from the client
BufferedReader inputStream = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
String inputData = inputStream.readLine();

// Process and respond to the received data 
String outputData = processData(inputData);
OutputStream outputStream = clientSocket.getOutputStream();

// Close the connection

Identifying the Service for Changing IoT Services

In order to make changes to IoT services, the appropriate service to use is the "Update" service. This service allows for updates to be made to the existing IoT services, as well as adding new services. The other options listed, such as "Enable", "Enable from Suspension", and "Registered Service Status" do not specifically refer to making changes to IoT services, but rather relate to the status and activation of services. Therefore, "Update" service is the correct answer for this question.

Language Used to Write Arduino IDE

The Arduino IDE has been written in C/C++, making use of the avr-gcc compiler and the AVRDUDE software for uploading code onto the microcontroller.

Identifying Short-Range IoT Networks

In the realm of IoT networks, there are various types of network systems used to enable communication between devices. One way to classify IoT networks is based on their range of coverage. Among the several types of IoT networks, those with short-range connectivity are limited to short distances. One such example is a short-range wireless network.

A short-range wireless network is a type of IoT network with limited geographical coverage. This network is of low energy and operates in a low frequency. For instance, Bluetooth, ZigBee, and WiFi-Direct are examples of short-range wireless communication technologies. These network solutions allow electronic devices to seamlessly exchange data over a short distance, without needing an internet connection.

Contrary to short-range wireless networks, LPWAN (Low Power Wide Area Networks) and Sigfox networks are long-range IoT networks with coverage of kilometers or miles. They are designed to enable communication with a broader geographical range and have increased penetration capabilities.

Therefore, depending on the requirements, specific IoT systems can be used to provide varying range distances between devices.

What is the Purpose of Web of Things (WoT)?

The purpose of Web of Things (WoT) is to improve the usability and interoperability of various connected devices by providing a common set of protocols and standards. WoT is designed to create a decentralized network of internet-enabled devices that can communicate and work together seamlessly. This makes it easier for consumers to use and control their connected devices, and for developers to create new applications and services that leverage the power of these devices.

API for controlling electronic components

Among the given options, the correct API for controlling electronic components is the RESTful API.


//Sample code for RESTful API for controlling electronic components

//Import required libraries
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

//Set endpoint URL for the electronic component
String endpoint = "http://example.com/electroniccomponent";

//Set command for controlling the electronic component
String command = "ON";

//Set the RESTful API URL using the endpoint and command
String restfulUrl = endpoint + "?command=" + command;

//Create HTTP connection using the RESTful API URL
URL url = new URL(restfulUrl);
HttpURLConnection con = (HttpURLConnection) url.openConnection();

//Read the response from the electronic component
BufferedReader in = new BufferedReader(
    new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {

//Print the response from the electronic component

Identifying a Lightweight Protocol

Out of the given options, the MQTT (Message Query Telemetry Transport) protocol is a lightweight protocol. It is designed to be used in IoT devices and has a minimal code footprint, making it ideal for low-power devices with limited processing power and memory. The protocol uses a publish-subscribe pattern and has a low overhead, allowing it to send messages efficiently.


Here is an example of how to use the Paho MQTT client to publish a message:

import paho.mqtt.client as mqtt

# Define event callbacks
def on_connect(client, userdata, flags, rc):
    print("Connection returned result: " + mqtt.connack_string(rc))

def on_publish(client, userdata, mid):
    print("Message {} published to topic {}".format(mid, userdata))

def on_disconnect(client, userdata, rc):
    if rc != 0:
        print("Unexpected disconnection.")

# Create a new MQTT client instance
client = mqtt.Client()

# Attach event callbacks
client.on_connect = on_connect
client.on_publish = on_publish
client.on_disconnect = on_disconnect

# Connect to the broker
client.connect("localhost", 1883, 60)

# Publish a message
result = client.publish("topic/test", "Hello, world!", qos=1)

# Wait for the publish operation to complete

# Disconnect from the broker


MQTT stands for Message Query Telemetry Transport.

Standard Port Number of Secure MQTT

According to the explanation, the standard port number for secure MQTT is 8883. Therefore, option D is the correct answer.

Range of Z-Wave

The range of Z-Wave is between 30-100 meters.

Identifying a Type of SPI Controller

In the list below, determine which of the following options represents a type of SPI controller:

  1. Data SPI
  2. Queued SPI
  3. Microwire
  4. Microwire or Plus

Answer: Queued SPI is a type of SPI controller.

Frequency Rate of Z-Wave

The correct frequency rate of the z-wave is 908.42 GHz.

Number of Capacitive Touch Sensors

There are two types of capacitive touch sensors: projected capacitive sensing and surface capacitive sensing. Therefore, the correct answer is A) 2.

Understanding IaaS

IaaS stands for Infrastructure as a Service. It is a cloud computing model that provides users with virtualized computing resources over the internet. In this model, users rent IT infrastructure, such as servers, storage, and networking, rather than buying and maintaining it themselves.

This allows businesses to scale their infrastructure easily and cost-effectively without investing in costly on-premises hardware. By utilizing cloud service providers that offer IaaS, organizations can focus on their core business operations and rely on the provider to take care of the underlying IT infrastructure.

Examples of IaaS providers include Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform (GCP).

It is important to note that IaaS is just one of several cloud computing models, including Platform as a Service (PaaS), Software as a Service (SaaS), and Function as a Service (FaaS).

//Sample code usage of IaaS provider AWS

Identifying Data Link Layer Technology

In computer networking, the data link layer is the second layer of the OSI model responsible for the transfer of data between adjacent network nodes in a wide area network (WAN) or local area network (LAN). The following technologies fall under the data link layer:

  • UART
  • Wi-Fi
  • Bluetooth

Therefore, the answer is D) HTTP, which is not a data link layer technology.

//JavaScript code to check if the technology is data link layer or not

function isDataLinkLayerTechnology(technology) {
  const dataLinkLayerTechnologies = ['UART', 'Wi-Fi', 'Bluetooth'];
  if(dataLinkLayerTechnologies.includes(technology)) {
    return `${technology} is a data link layer technology.`;
  } else {
    return `${technology} is not a data link layer technology.`;

console.log(isDataLinkLayerTechnology('HTTP')); // Output: HTTP is not a data link layer technology.

DHCP Transport Layer Protocol

The transport layer protocol used by DHCP is UDP.

  // Sample code illustrating the use of UDP in DHCP

  import java.net.*;

  public class DHCPClient {
    public static void main(String[] args) {
      try {
        // create a UDP socket 
        DatagramSocket clientSocket = new DatagramSocket();
        // create a request packet
        byte[] requestData = new byte[1024];
        InetAddress serverAddress = InetAddress.getByName("server_ip_address");
        DatagramPacket requestPacket = new DatagramPacket(requestData, requestData.length, serverAddress, 67);
        // send the request packet
        // receive the response packet
        byte[] responseData = new byte[1024];
        DatagramPacket responsePacket = new DatagramPacket(responseData, responseData.length);
        // process the response
        String responseString = new String(responsePacket.getData());
      } catch (Exception e) {

Identifying the Port Layer in the OSI Model

According to the OSI (Open Systems Interconnection) model, the port layer is located at the Session layer. Therefore, the correct answer to this question is C) Session. The port layer is the fifth layer of the OSI Model, which is responsible for establishing, maintaining, and terminating the connections between applications running on different network devices.

Identifying Non-Networking Devices

The traffic analyzer is not considered a networking device as it is not responsible for forwarding or routing data packets across different networks. Instead, it is used to monitor and analyze network traffic to help identify issues and improve network performance. On the other hand, switches, routers, and bridges are all networking devices that are essential to the functioning of modern computer networks.

// No code to optimize as this is a knowledge-based explanation

Checking if an IoT network is a collection of interconnected devices

The statement "An IoT network is a collection of interconnected devices" is true. An IoT network consists of multiple devices such as sensors, actuators, and other IoT devices that are interconnected to each other via the internet or other communication channels. These devices can communicate with each other and exchange data, which can be collected, analyzed, and used to make informed decisions.

Answer: True

Arduino UNO: A Hardware Device

The correct answer is D, Arduino UNO is a hardware device. It is a popular microcontroller board that is used to create various electronic projects. It is equipped with digital and analog input/output pins, easy-to-use USB interface, and a power jack. The device allows programming in C/C++, and it is suitable for both beginners and experienced developers. In short, Arduino UNO is a valuable hardware tool for prototyping and DIY electronics.


The correct answer for the given question is option B, which is Inter-Integrated Communication. I2C is a serial communication protocol that is widely used to connect microcontrollers to peripherals such as sensors, memory devices, and other microcontrollers. It is a two-wire communication protocol that uses a Master-Slave architecture and supports multiple slaves.


MQTT is based on a publish-subscribe architecture, where publishers send messages to a broker, and subscribers receive messages from the broker. This architecture enables lightweight communication between devices and is highly scalable.

// Example code demonstrating MQTT publish-subscribe architecture
// Import necessary libraries
import paho.mqtt.client as mqtt

# Define callbacks
def on_connect(client, userdata, flags, rc):
    if rc == 0:
        print("Connected to broker")
        print("Connection failed")

def on_publish(client, userdata, mid):
    print("Message published")

def on_message(client, userdata, msg):
    print(f"Received message: {msg.payload.decode()}")

# Create client
client = mqtt.Client()

# Set up callbacks
client.on_connect = on_connect
client.on_publish = on_publish
client.on_message = on_message

# Connect to broker and subscribe to topic

# Publish message
client.publish("example/topic", "Hello, world!")

# Disconnect from broker

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