PG-S4-Msc. AI, Internet of Things, First Internal Examination, January 2024

 

AI800404 -INTERNET OF THINGS

1. Define IOT

IoT stands for Internet of Things. It refers to the interconnectedness of physical devices, such as appliances and vehicles, that are embedded with software, sensors, and connectivity which enables these objects to connect and exchange data. This technology allows for the collection and sharing of data from a vast network of devices, creating opportunities for more efficient and automated systems.

2. Compare and contrast MQTT and COAP?

MQTT (Message Queuing Telemetry Transport) and CoAP (Constrained Application Protocol) are both protocols designed for efficient communication in the context of the Internet of Things (IoT) and machine-to-machine (M2M) communication. While they share some similarities, there are also significant differences between them. Here's a comparison:

Similarities:

1.    Lightweight:

·      Both MQTT and CoAP are designed to be lightweight protocols suitable for resource-constrained devices, making them well-suited for IoT devices with limited processing power and memory.

2.    Asynchronous Communication:

·      Both protocols support asynchronous communication, allowing devices to send and receive messages independently.

3.    Publish-Subscribe Model:

·      Both MQTT and CoAP support a publish-subscribe model, where devices can publish information to specific topics, and other devices can subscribe to those topics to receive updates.

Differences:

1.    Protocol Layers:

·      MQTT operates at the application layer of the OSI model, while CoAP operates at the application layer but also includes a lightweight transaction layer.

2.    Transport Protocol:

·      MQTT typically uses TCP as its underlying transport protocol, providing reliable communication but with potentially higher overhead due to the connection-oriented nature of TCP.

·      CoAP, on the other hand, is designed to work over UDP, which is connectionless. This makes CoAP more suitable for scenarios where low-latency and lower overhead are critical.

3.    Communication Model:

·      MQTT is based on a client-server model where clients communicate with a central broker. The broker is responsible for managing the messages and routing them to the appropriate subscribers.

·      CoAP can work in a client-server model, but it also supports a more decentralized approach where devices communicate directly with each other without the need for a central server or broker.

4.    Reliability:

·      MQTT ensures reliability through its use of TCP, which provides a reliable, connection-oriented communication. However, this may result in higher overhead and increased latency.

·      CoAP, being based on UDP, is designed for scenarios where low overhead is more important than guaranteed delivery. It provides optional reliability through the use of mechanisms like Confirmable (CON) messages.

5.    Security:

·      Both MQTT and CoAP support security features. MQTT often relies on external security mechanisms, such as TLS/SSL, for secure communication.

·      CoAP includes a lightweight security model, typically using Datagram Transport Layer Security (DTLS) to secure communications.

6.    Resource Discovery:

·      CoAP includes built-in support for resource discovery, allowing clients to dynamically discover resources on a server.

·      MQTT relies on predefined topics, and discovery mechanisms may need to be implemented separately.

3. With suitable syntax how to create a table in MYSQL?

CREATE TABLE your_table_name (

    column1_name datatype1,

    column2_name datatype2,

    column3_name datatype3,

    ...,

    PRIMARY KEY (one_or_more_columns)

);

4. What is 6LoWPAN?

6LoWPAN is an IPv6 protocol, and It’s extended from is IPv6 over Low Power Personal Area Network. As the name itself explains the meaning of this protocol is that this protocol works on Wireless Personal Area Network i.e., WPAN.

WPAN is a Personal Area Network (PAN) where the interconnected devices are centered around a person’s workspace and connected through a wireless medium. You can read more about WPAN at WPAN. 6LoWPAN allows communication using the IPv6 protocol. IPv6 is Internet Protocol Version 6 is a network layer protocol that allows communication to take place over the network. It is faster and more reliable and provides a large number of addresses.

6LoWPAN initially came into existence to overcome the conventional methodologies that were adapted to transmit information. But still, it is not so efficient as it only allows for the smaller devices with very limited processing ability to establish communication using one of the Internet Protocols, i.e., IPv6. It has very low cost, short-range, low memory usage, and low bit rate.

5. Explain any 2 applications of IOT?

Smart Home Automation

Industrial IoT (IIoT) for Predictive Maintenance

Section B

Answer any 3 questions. Weight 2 each.

6. Explain COAP?

CoAP, which stands for Constrained Application Protocol, is a specialized web transfer protocol designed for constrained devices and constrained networks within the Internet of Things (IoT) context. The term "constrained" refers to devices with limited processing power, memory, and bandwidth. CoAP is designed to provide a lightweight and efficient communication protocol that can operate effectively in resource-constrained environments.

7.  What is M2M?

M2M stands for Machine-to-Machine, and it refers to direct communication between devices or machines without human intervention. In M2M communication, machines exchange data and information with each other to perform tasks, make decisions, or coordinate actions. The goal is to enable intelligent and autonomous interactions between devices, enhancing efficiency, automation, and overall system functionality.

8. What is the web of things and how it is related to IOT?

                                               The Web of Things (WoT) is an approach and set of standards that extends the World Wide Web architecture to seamlessly integrate and interconnect various devices and systems in the Internet of Things (IoT). WoT aims to make IoT devices and services more accessible, interoperable, and usable on the web by providing a standardized framework for describing, consuming, and interacting with IoT resources.

Now, regarding the relationship between the Web of Things and the Internet of Things (IoT):

·      WoT as an Enabler for IoT:

·      The Web of Things provides a standardized approach to make IoT devices and services part of the web architecture. It extends the principles of the web to the IoT, making it easier to discover, access, and interact with a wide range of devices.

·      Interoperability and Integration:

·      WoT contributes to the goal of interoperability in the IoT landscape. By standardizing the description and interaction models, WoT enables devices from different manufacturers to work together seamlessly.

·      User-Friendly Interaction:

·      The integration of WoT with web technologies allows for the creation of user-friendly interfaces for controlling and monitoring IoT devices. Users can interact with WoT-enabled devices through web browsers and applications, promoting a consistent and familiar user experience.

9. Explain REST Protocol.

REST, which stands for Representational State Transfer, is an architectural style for designing networked applications. It was introduced by Roy Fielding in his doctoral dissertation in 2000. REST is not a protocol itself but a set of principles and constraints that can be applied to design scalable, stateless, and loosely coupled web services. RESTful web services are commonly built on top of the HTTP protocol, but the principles can be applied to other protocols as well.

Section C

Answer any 1 question. Weight 5

10.  Briefly Explain IOT Architecture with a neat diagram.

11. Explain MQTT?

MQTT (Message Queuing Telemetry Transport) is a lightweight, open-source messaging protocol that is designed for efficient communication in situations where low bandwidth, high latency, or an unreliable network is expected. MQTT is widely used in the Internet of Things (IoT) and M2M (Machine-to-Machine) communication.

Key features of MQTT include:

1.   Publish-Subscribe Model:

·      MQTT follows a publish-subscribe communication model. In this model, devices (called clients) can either publish messages to a specific topic or subscribe to receive messages on a specific topic. The broker is responsible for managing the communication between publishers and subscribers.

2.   Asynchronous Communication:

·      MQTT enables asynchronous communication, allowing devices to send and receive messages independently. This is particularly useful in scenarios where devices need to operate independently or where real-time communication is essential.