Web Communication

In this blog post, we'll take a deep dive into the inner workings of websites, demystifying the technical aspects and providing a clear understanding of how they function. From the client-server model to the flow of data, we'll explore the key components and processes that enable websites to come to life.

The Client-Server Model:

• Understanding the basic architecture of the web.

• Exploring the roles of clients (web browsers) and servers.

• Communication protocols: HTTP and HTTPS.

What is the basic architecture of web?

The basic architecture of the web is commonly referred to as the client-server model. It is a distributed system where web resources, such as websites and web applications, are accessed and delivered through a network. Here's an overview of the basic architecture:

1. Clients: Clients are devices used by users to access and view websites. They typically include web browsers such as Chrome, Firefox, Safari, or Edge. Clients send requests to servers and receive responses containing web content.

2. Servers: Servers are powerful computers or systems that store and deliver web resources. They receive requests from clients, process them, and send back the requested information as responses. Servers are responsible for hosting websites and handling various tasks like processing server-side code and accessing databases.

3. Communication Protocols: The primary communication protocol used on the web is HTTP (Hypertext Transfer Protocol). It defines the rules and formats for requesting and delivering web resources. HTTPS (HTTP Secure) is a secure version of HTTP that encrypts data transmission, providing an extra layer of security.

4. Request-Response Cycle: The interaction between clients and servers follows a request-response cycle. Clients send requests to specific URLs (Uniform Resource Locators) using HTTP methods like GET (retrieve data), POST (submit data), PUT (update data), DELETE (remove data), and more. Servers process these requests, generate appropriate responses, and send them back to the clients.

5. Front-End and Back-End: Web development is divided into front-end and back-end components. Front-end development focuses on creating the user interface and client-side functionality using technologies like HTML, CSS, and JavaScript. Back-end development deals with server-side programming, database management, and other behind-the-scenes tasks using languages like PHP, Python, Ruby, or Java.

6. Hosting and Domain Names: Websites are hosted on servers, which store website files and make them accessible over the internet. Domain names, such as www.example.com, provide a human-readable address for accessing websites. DNS (Domain Name System) is responsible for translating domain names into IP addresses, which servers use to route requests.

Understanding the basic architecture of the web is essential for grasping how websites function and how various components interact to deliver web content to users.

what is the role of a client and servers?

The roles of clients and servers are fundamental in the client-server model of web architecture. Here's an explanation of the roles they play:

1. Clients: Clients refer to the devices or applications used by users to access and interact with websites or web applications. Common examples of clients include web browsers (such as Chrome, Firefox, Safari) running on desktop computers, laptops, smartphones, or tablets. The primary role of clients is to send requests to servers and receive responses containing web content.

The responsibilities of clients include:

• Initiating requests: Clients send requests to servers by specifying the URL (Uniform Resource Locator) of the desired resource, such as a web page, image, or API endpoint.

• Displaying web content: Clients interpret the received responses from servers and render the web content, presenting it to the user in a visually appealing and interactive manner.

• Executing client-side code: Clients execute client-side technologies like HTML, CSS, and JavaScript to render and enhance the user interface, handle user interactions, and perform various front-end functionalities.

1. Servers: Servers are powerful computers or systems that store and deliver web resources requested by clients. They handle incoming requests, process them, and send back appropriate responses. Servers are responsible for hosting websites, handling server-side processing, accessing databases, and managing various back-end operations.

The responsibilities of servers include:

• Receiving and processing requests: Servers receive requests sent by clients and analyze them to determine the required action or resource.

• Generating responses: Based on the received requests, servers generate appropriate responses containing the requested web content or perform the necessary operations before sending the responses back to clients.

• Serving web resources: Servers store and deliver web resources, such as HTML pages, images, stylesheets, scripts, and data, to clients upon request.

• Performing server-side processing: Servers execute server-side programming languages (e.g., PHP, Python, Ruby) to handle complex computations, interact with databases, and process data before sending the final responses to clients.

In summary, clients initiate requests, display web content, and execute client-side code, while servers receive requests, generate responses, serve web resources, and perform server-side processing. The collaboration between clients and servers enables the functioning of websites and the delivery of web content to users.

what is a http/https communication protocol, and how it works internally?

HTTP (Hypertext Transfer Protocol) and its secure counterpart HTTPS (HTTP Secure) are widely used communication protocols for transmitting data over the internet. They define the format and rules for requesting and delivering web resources, such as web pages, images, and files. Here's an overview of how HTTP/HTTPS works internally:

1. Client-Server Interaction:

   • A client, typically a web browser, initiates an HTTP request by specifying a URL (Uniform Resource Locator) in the address bar or clicking on a link.

   • The client establishes a TCP/IP (Transmission Control Protocol/Internet Protocol) connection with the server at the specified domain name or IP address. This connection is made on port 80 for HTTP or port 443 for HTTPS.

   • If using HTTPS, the client and server perform a handshake process to establish a secure encrypted connection using SSL/TLS (Secure Sockets Layer/Transport Layer Security) protocols. This ensures that the data transmitted between the client and server remains confidential and secure.

2. HTTP Request:

   • The client sends an HTTP request to the server, which includes:

     • The HTTP method, such as GET, POST, PUT, or DELETE, indicates the desired action to be performed.

     • The requested URL and the specific resource path on the server.

     • Optional headers that provide additional information, such as user-agent, content type, and cookies.

     • If applicable, a request body containing data (e.g., form inputs) for POST or PUT methods.

3. Server Processing:

   • The server receives the HTTP request, interprets its components, and performs the requested action.

   • The server may interact with databases, execute server-side scripts, or retrieve static resources to generate the response.

   • The server constructs an HTTP response, including:

     • A response status code indicating the outcome of the request (e.g., 200 for successful, 404 for not found).

     • Response headers provide metadata and instructions for the client.

     • The response body contains the requested resource or appropriate data (e.g., HTML, JSON, images).

4. HTTP Response:

   • The server sends the HTTP response back to the client over the established connection.

   • The client receives the response and checks the status code to determine the success or failure of the request.

   • The client interprets the response headers and processes the response body accordingly.

   • The client renders the received content, displaying the requested web resource or performing additional actions based on the response data.

Throughout the process, HTTP/HTTPS protocols handle data transfer, communication errors, and other aspects of the transmission. HTTPS adds an additional layer of security by encrypting the data exchanged between the client and server using SSL/TLS.

By adhering to the HTTP/HTTPS protocol, web browsers and servers can communicate effectively, allowing users to access and interact with web resources securely and reliably.

It may feel like little overwhelming to hear a lot of technical aspects that how a website works, but it's ok to not know these things through progressive learning by curiosity you can easily know about that technical aspects and believe me it is joyful to know how the things work whether it's a website or our neighbour internal matter(lol) or how our government work internally.

Request-Response Cycle:

• A step-by-step breakdown of the request-response cycle.

• User-initiated requests: typing URLs, clicking links, submitting forms.

• Server-side processing and generating responses.

step-by-step breakdown of the request-response cycle:

The request-response cycle is a fundamental process in web communication where a client sends a request to a server, and the server responds with the requested data. Here's a step-by-step breakdown of the request-response cycle:

1. Client Initiates the Request:

   • The client, typically a web browser, initiates the request by sending an HTTP request to a specific URL (Uniform Resource Locator).

   • The client may click on a link, submit a form, or directly enter the URL in the browser's address bar.

2. DNS Resolution (if applicable):

   • If the URL contains a domain name, the client performs a DNS (Domain Name System) resolution to obtain the corresponding IP address of the server hosting the website.

   • The DNS system maps the human-readable domain name (e.g., www.example.com) to its corresponding IP address (e.g., 192.0.2.123).

3. Establishing a Connection:

   • The client establishes a TCP/IP (Transmission Control Protocol/Internet Protocol) connection with the server using the server's IP address and the specified port number (typically port 80 for HTTP or port 443 for HTTPS).

   • For HTTPS, an additional step of establishing a secure encrypted connection using SSL/TLS (Secure Sockets Layer/Transport Layer Security) protocols is performed.

4. Sending the Request:

   • The client sends an HTTP request to the server over the established connection.

   • The request includes the HTTP method (e.g., GET, POST, PUT, DELETE) indicating the desired action, the requested URL, optional headers, and, if applicable, a request body containing data.

5. Server Processing:

   • The server receives the HTTP request and processes it.

   • The server interprets the request, retrieves necessary data from databases or performs other operations to generate the response.

6. Preparing the Response:

   • The server constructs an HTTP response, including a response status code indicating the outcome of the request (e.g., 200 for success, 404 for not found).

   • The server adds response headers that provide metadata and instructions for the client.

   • The server includes the response body containing the requested resource or appropriate data (e.g., HTML, JSON, images).

7. Sending the Response:

   • The server sends the HTTP response back to the client over the established connection.

   • The response includes response headers and the response body.

8. Receiving and Processing the Response:

   • The client receives the response from the server.

   • The client checks the response status code to determine the success or failure of the request.

   • The client processes the response headers, extracting metadata and instructions.

   • The client interprets the response body, rendering the received content or performing additional actions based on the data.

9. Closing the Connection:

   • After the response is received and processed, the client closes the TCP/IP connection with the server.

The request-response cycle enables the exchange of information between clients and servers, allowing users to access and interact with web resources. It forms the backbone of web communication, facilitating the dynamic and interactive nature of the web.

User-initiated requests refer to actions performed by users that trigger HTTP requests to be sent from the client (web browser) to the server. These requests are typically initiated through user interactions with the web application or website. Here are three examples of user-initiated requests:

what are User-initiated requests: typing URLs, clicking links, submitting forms?

1. Typing URLs:

   • Users can initiate an HTTP request by directly typing a URL (Uniform Resource Locator) into the browser's address bar.

   • For example, entering "https://www.example.com" in the address bar and pressing Enter triggers the browser to send an HTTP request to the server hosting the website at that specific URL.

2. Clicking Links:

   • Users can navigate through web pages by clicking on hyperlinks or links provided within the content.

   • When a user clicks on a link, the browser interprets it as a signal to initiate an HTTP request for the linked resource.

   • For instance, clicking on a navigation menu item or an article headline on a webpage triggers the browser to send an HTTP request to retrieve the linked page or resource.

3. Submitting Forms:

   • Websites often include forms that allow users to input data and submit it to the server for processing.

   • When a user fills out a form (e.g., a login form, a search form, or a contact form) and clicks the submit button, the browser sends an HTTP request to the server with the form data.

   • The server processes the request, performing actions such as authentication, search queries, or storing the submitted data.

User-initiated requests are essential for user engagement and interaction with web applications. They enable users to access specific URLs, navigate through different pages, and interact with dynamic content by submitting data. The web browser acts as the intermediary, sending the appropriate HTTP requests to the server based on the user's actions, and receiving the corresponding responses to display the requested content or perform the desired functionality.

what is Server-side processing and generating responses?

Server-side processing refers to the execution of code and handling of data on the server in response to client requests. When a server receives a request from a client, it performs various operations and generates an appropriate response to fulfil the client's request. Here's an explanation of server-side processing and response generation:

1. Request Handling:

   • The server receives the client's HTTP request, which contains information about the requested resource, data, and additional headers.

   • The server processes the request by extracting relevant details, such as the requested URL, query parameters, form data, or any authentication credentials.

   • The server may interact with databases, external APIs, or other resources to retrieve or manipulate data necessary to fulfil the request.

2. Business Logic and Processing:

   • Server-side processing involves executing the server-side code or scripts written in server-side programming languages like PHP, Python, Ruby, or Java.

   • The server-side code performs various operations, computations, and manipulations on the data received from the client or retrieved from databases.

   • Business logic is applied to validate inputs, process user data, perform calculations, apply security measures, or interact with external systems.

3. Data Manipulation and Integration:

   • Server-side processing often involves data manipulation, transformation, or integration tasks.

   • The server may process and sanitize user input to prevent security vulnerabilities like SQL injection or cross-site scripting (XSS) attacks.

   • Data validation, parsing, and formatting can be performed to ensure the accuracy and consistency of the data.

   • Integration with external systems or APIs may occur to retrieve additional data or perform specific actions.

4. Response Generation:

   • After the server-side processing and data manipulation, the server generates an HTTP response to send back to the client.

   • The response typically includes a response status code indicating the outcome of the request (e.g., 200 for success, 404 for not found).

   • The server adds response headers containing metadata, caching instructions, content type, and other relevant information.

   • The server includes the response body, which holds the requested resource (e.g., HTML markup, JSON data) or a relevant message based on the request.

Server-side processing allows the server to handle complex operations, interact with databases and external resources, apply business rules, and generate appropriate responses to fulfil client requests. This enables dynamic, data-driven, and personalized experiences on the web.

This is the whole idea of how a website work internally and from outside too. you can see how HTTP/https I am using in this whole blog content The reason HTTP/HTTPS is mentioned repeatedly in the blog/article is that it is a crucial part of web communication and understanding how websites work. HTTP (Hypertext Transfer Protocol) and HTTPS (HTTP Secure) are the standard protocols used for transmitting data between clients (web browsers) and servers over the internet.HTTP is the foundation of web communication and defines the format and rules for requesting and delivering web resources. It specifies how clients and servers should interact, what information should be included in requests and responses, and how data should be transmitted.

so from the next blog, we will know about frontend and backend development as per my experience, and if you want to give me any feedback then feel free to do I will respect your opinion and will try to improve my content.

thank you for reading this blog/article, please do subscribe if you like