Client Server Model

Client-Server Model in Website

  • Definition: The client-server model is a fundamental architecture in web development, involving two main components: the client (user's device) and the server (remote computer hosting the website).
  • Client (Frontend):
    • Device (e.g., computer, smartphone) and web browser.
    • Responsibilities: Rendering UI, handling user interactions.
    • Technologies: HTML, CSS, JavaScript.
  • Server (Backend):
    • Remote computer hosting the website.
    • Responsibilities: Handling requests, executing server-side logic, generating responses.
    • Technologies: Server-side languages (e.g., Node.js), databases (e.g., MongoDB).
  • Request-Response Cycle:
    • User interacts with the website.
    • Client sends requests to the server.
    • Server processes requests, executes logic, and sends back responses.
    • Client renders the received content.
  • Communication Protocols:
    • HTTP/HTTPS for client-server communication.
    • WebSockets for real-time bidirectional communication.
  • Security (HTTPS):
    • Ensures secure data transmission using encryption.
    • Utilizes SSL/TLS protocols.

Types of Client-Server Architecture: 1 Tier Model

tier 1 client server architecture

Ref: https://www.prepbytes.com/blog/dbms/dbms-architecture/

  • Definition: The 1-tier client-server model is the simplest architecture where both the client and server components reside on the same machine.
  • Single Machine:
    • Client-side and server-side components coexist on the user's device.
  • Responsibilities:
    • Client handles user interface and interactions.
    • Server manages data processing and application logic.
  • Use Cases:
    • Typically used for small, standalone applications.
    • Common in desktop applications where both UI and logic run locally.
  • Advantages:
    • Simplicity and ease of development.
    • Minimal network communication overhead.
  • Disadvantages:
    • Limited scalability.
    • May not suit distributed or large-scale applications.
  • Example:
    • A simple calculator application where the UI and calculation logic both run on the user's machine.

Types of Client-Server Architecture: 2 Tier Model

Ref: https://upload.wikimedia.org/wikipedia/commons/8/85/Client-Server_2-tier_architceture_-_en.png/

  • Definition: The 2-tier client-server model involves two main components - the client, responsible for the user interface, and the server, handling data processing and storage.
  • Client Tier:
    • Responsible for the presentation layer and user interface.
    • Interacts directly with the user.
    • Executes application logic related to the user interface.
  • Server Tier:
    • Manages data processing and storage.
    • Executes application logic related to data management.
    • Typically hosts a database for persistent data storage.
  • Communication:
    • Communication between the client and server involves direct requests and responses.
    • The client sends requests for data or operations, and the server responds accordingly.
  • Use Cases:
    • Commonly used for small to medium-sized applications.
    • Suitable for scenarios where data processing and user interface can be logically separated.
  • Advantages:
    • Clear separation of concerns between user interface and data processing.
    • Easier to maintain than a 1-tier model.
  • Disadvantages:
    • Limited scalability as both tiers are tightly coupled.
    • Challenges with concurrent user access in certain scenarios.
  • Example:
    • A simple web application where the browser (client) interacts with a server hosting a database (server) to retrieve and store data.

In summary, the 2-tier client-server model introduces a separation between the user interface (client) and data processing (server), allowing for more organized development in comparison to the 1-tier model.

Types of Client-Server Architecture: 3 Tier Model

  • Definition: The 3-tier client-server model involves three main components - the client (presentation), application server (logic), and database server (data).
  • Client Tier (Presentation):
    • Handles the user interface and user interactions.
    • Displays information and captures user input.
    • Executes presentation logic.
  • Application Server Tier (Logic):
    • Manages application logic and business rules.
    • Processes user requests and performs necessary computations.
    • Acts as an intermediary between the client and the database.
  • Database Server Tier (Data):
    • Stores and retrieves data.
    • Manages data integrity and security.
    • Executes database-related operations.
  • Communication:
    • Clients communicate with the application server for application logic.
    • Application server communicates with the database server for data operations.
    • Promotes a clear separation of concerns.
  • Use Cases:
    • Suitable for larger, more complex applications.
    • Enhances scalability and maintainability.
    • Allows for distributed development and specialization.
  • Advantages:
    • Improved organization and modularity.
    • Easier maintenance and updates.
    • Scalability due to separation of concerns.
  • Disadvantages:
    • Increased complexity compared to 2-tier models.
    • Potential for increased network latency.
  • Example:
    • An e-commerce website where the browser (client) interacts with an application server for business logic, which in turn interacts with a database server for data retrieval and storage.