Level 2 Tasks Report by Darshan

14 / 9 / 2024

Task 1 - OSI

1. Layered Structure

The OSI model divides network communication into seven distinct layers, each with specific functions:

• Physical Layer: Manages the physical transmission of data over a medium.
• Data Link Layer: Handles node-to-node data transfer and error correction.
• Network Layer: Manages logical addressing and routing between different networks.
• Transport Layer: Ensures reliable end-to-end communication with error checking and flow control.
• Session Layer: Manages sessions between applications, including synchronization and recovery.
• Presentation Layer: Translates, encrypts, and compresses data for readability between systems.
• Application Layer: Interfaces directly with user applications and provides network services.

2. Network Protocols

Network protocols define rules for data communication, ensuring effective device interaction:

• Ethernet: Facilitates LAN data transmission.
• TCP/IP: Backbone of internet communication, ensuring reliable data delivery.
• HTTP/HTTPS: For web page and secure data transmission.
• SMTP: Used for email transfer.
• DNS: Translates domain names into IP addresses.
• FTP: Enables file transfers.

3. Routing and Switching

• Routing: Routers at the Network Layer determine the best path for data packets across multiple networks, utilizing routing tables to optimize data delivery.
• Switching: Switches at the Data Link Layer forward data frames within a LAN based on MAC addresses. Unlike routing, switching handles local network data forwarding.

4. Handshakes

• Two-Way Handshake: Establishes a basic connection with synchronization and acknowledgment messages. Potential issues include delayed acknowledgments.
• Three-Way Handshake: Uses SYN, SYN-ACK, and ACK steps to ensure a reliable connection, addressing issues like SYN duplication errors.

5. IP Addressing

• IPv4: Format of four decimal numbers (e.g., 192.155.12.1).
• IPv6: Format of eight hexadecimal numbers (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334).

6. Advantages of the OSI Model

• Simplification: Breaks down network communication into manageable layers.
• Standardization: Ensures consistency and compatibility across systems.
• Troubleshooting: Simplifies problem diagnosis by isolating issues to specific layers.
• Flexibility: Allows independent updates and improvements to various layers.

Task 2 - Serverless

1. Understanding Serverless Architecture

• Functions as a Service (FaaS): Abstracts server management from developers, focusing on code execution. Billing is based on function invocations and compute time, with automatic scaling based on demand.

2. AWS Lambda

• Overview: AWS Lambda executes code in response to events, eliminating server management and scaling automatically based on requests.
• Key Features: Event-based execution, automatic scaling, and cost efficiency based on actual compute time.

3. AWS API Gateway

• Role: Provides REST endpoints to trigger Lambda functions, simplifying API creation, management, and integration with Lambda.

4. Serverless Framework

Purpose: A toolkit that simplifies the deployment and management of serverless applications, focusing on code rather than infrastructure.

Installation and Setup:

• Install globally with npm install -g serverless.
• Configure with AWS credentials and create a service using a Serverless template.
• Deployment: Use serverless deploy to package and deploy the service.

5. Testing Locally with Serverless Offline

• Setup: Initialize npm with npm init, install Serverless Offline using npm install serverless-offline --save-dev, and configure serverless.yml to include serverless-offline.
• Running Locally: Use serverless offline start to start local emulation and test the Lambda function.

Conclusion

The coursework highlights serverless computing with Node.js, focusing on:

• FaaS: Server management abstraction and automatic scaling.
• AWS Lambda: Event-driven execution with cost-efficient billing.
• AWS API Gateway: Simplified API management.
• Serverless Framework: Deployment and management ease.
• Serverless Offline: Local testing and development streamlining.

Task 3 - Sockets!

1. Understanding WebSockets

• Definition: WebSockets enable full-duplex communication channels over a single TCP connection, providing real-time data exchange.
• Benefits: Real-time communication, persistent connection, and efficient data transmission with lower latency and reduced overhead.

How It Works:

• Handshake Process: Client initiates a connection with an Upgrade header, server responds with HTTP 101, and the connection is upgraded for bidirectional communication.

2. Socket.IO Overview

• Definition: Socket.IO is a library for real-time web applications, supporting bidirectional and event-based communication. It provides additional features beyond WebSockets, such as automatic reconnections and event handling.

3. Building a Real-Time Chat Application

Client-Side Implementation:

var socket = io();
$("form").submit(function (e) {
  e.preventDefault();
  socket.emit("chat message", name + ": " + $("#m").val());
  $("#messages").append($('').text("You: " + $("#m").val()));
  $("#m").val("");
  return false;
});
socket.on("chat message", function (msg) {
  $("#messages").append($("").text(msg));
});

Server-Side Implementation:

io.on("connection", (socket) => {
  console.log("new user connected");

  socket.on("joining msg", (username) => {
    name = username;
    io.emit("chat message", `___${name} joined the chat___`);
  });

  socket.on("disconnect", () => {
    console.log("user disconnected");
    io.emit("chat message", `___${name} left the chat___`);
  });

  socket.on("chat message", (msg) => {
    socket.broadcast.emit("chat message", msg);
  });
});

Conclusion

The course on Socket.io and real-time communication provided:

• WebSocket Protocol: Full-duplex communication with lower latency and overhead.
• Socket.IO: Enhanced features for real-time applications.
• Practical Implementation: Building and handling real-time chat applications with Socket.IO.

Task 4 - Make a Web app

1. Overview

The Resource Library Website project aims to manage and access library resources through an online platform. Key features include:

• Library Dashboard: Displays library statistics and resource details.
• Cataloging and Classification: Organizes materials with unique identifiers and categories.
• User Account Management: Manages user accounts and notifications for overdue items.
• Search and Browse: Enables searching by title, author, genre, ISBN, and publisher.

2. Technologies Used

• Node.js / Express.js: Scalable network applications and server management.
• Pug / Jade Templating Engine: Dynamic HTML content rendering.
• MongoDB Atlas: Cloud-based NoSQL database service.
• Mongoose ODM: Schema validation and data management with MongoDB.
• Git & GitHub: Version control and collaboration.
• Glitch: Online IDE and hosting for JavaScript and Node.js.

3. Practical Implementation

• Development Environment: Install Node.js, clone the repository, and install dependencies.
• Running Locally: Use specific commands based on your OS to start the server.
• Accessing the Application: Navigate to http://localhost:3000/ to interact with the site.

4. Development Workflow

• Code Management: Track changes and collaborate with Git and GitHub.
• Dynamic Content: Use Pug for server-side HTML rendering.
• Database Management: Manage data with MongoDB and Mongoose.
• Deployment: Use Glitch for instant hosting and deployment.

Conclusion

The Resource Library Website project emphasized:

• Technology Integration: Effective use of Node.js, Express.js, Pug, MongoDB, and Mongoose.
• Development Workflow: Setting up environments, managing code, and deploying applications.
• Practical Features: Implementing cataloging, user management, and search functionalities.