Client-Server-Architecture-The-Foundation-of-Modern-Computing.pptx

Client–Server Architecture (Short Summary)

Client–Server Architecture is a model in which multiple client devices (like computers, phones, or applications) request services or data from a central server.

Client: The device or program that makes a request.
Example: Your browser (Chrome/Firefox) asking for a webpage.

Server: A more powerful computer that processes the request and returns the response.
Example: A web server sending you the website content.



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Key Features

Client Server

Sends requests Receives and processes requests
Is often a user's device Usually centralized and powerful
Depends on server responses Stores data and provides services



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Why It Matters

This model is the backbone of modern internet and applications, including:

Websites

Online banking

Email services

Cloud applications


It improves efficiency, centralizes data, and allows multiple users to access shared resources over a network.

1. Client-Server Architecture: The Foundation of Modern Computing Client-server architecture is a fundamental computing model where a central server hosts and manages resources and services for one or more client computers connected over a network. Core Components and Connectors 1 Clients Software or applications that initiate the interaction by taking user input and sending requests for resources to the server. 2 Servers A software component or machine responsible for receiving, processing, and fulfilling requests originating from the clients. 3 Load Balancer Optimizes resource usage by efficiently distributing incoming network traffic across a group of available backend servers. 4 Network Protocols Governing rules, such as TCP/IP, that facilitate the orderly and reliable exchange of data between clients and servers. Also known as a networking computing model, this architecture defines how requests and services are delivered across a network.

2. The Unidirectional Data Flow Cycle The client-server communication process forms a continuous, unidirectional cycle, typically initiated by a client request and completed by a server response. 1 Client Request The client initiates the exchange by requesting specific data or a service from the network. 2 Traffic Routing The Load Balancer intercepts the request and efficiently routes it to the most appropriate, available server. 3 Server Processing The selected server begins processing the client's request, often involving complex computational tasks. 4 Database Query The server queries the relevant database systems (e.g., SQL/Cache) to retrieve the necessary information. 5 Data Retrieval The queried data is returned from the database back to the server for final preparation. 6 Response to Client The server processes the retrieved data, formats the final response, and sends it back to the client via the governing protocol. Note: Clients cannot communicate directly with each other; all communication must be mediated through the central server.

3. Why Client-Server Architecture Matters This architectural style is most useful for applications requiring clear separation of concerns and high interoperability, enabling systems to improve performance and scale efficiently. Separation of Functionality Client Layer: Handles user interface, request validation, and input. Server Layer: Dedicated to processing requests, database interaction, and return results. Layers operate independently, abstracting complex functionality (e.g., a client doesn't need to know how the server handles authentication). Enhanced Scalability and Performance Improved Efficiency at Scale The independent nature of the layers allows each part to function and optimize more efficiently under heavy load. Scalability Techniques Modern approaches like load balancing, sharding, and partitioning are employed to handle multiple simultaneous requests efficiently. System Optimization These techniques provide critical performance improvements, essential for software that supports a large number of users or high transaction volumes.

4. Trade-offs and Operational Challenges While robust, the client-server model introduces specific risks related to centralization and high operational costs. Centralized Risk of Failure Administrative Hub: Servers are essential for administering the entire setup and service delivery. Single Point of Failure: If the server infrastructure experiences an outage, the entire service becomes unavailable to all clients. Vulnerability to Attacks The centralized nature makes the architecture vulnerable to Denial of Service (DoS) attacks. DoS Attack: A perpetrator floods the server resource with requests to overload the system, preventing legitimate requests from being fulfilled. DDoS Attack (Distributed DoS): The attack traffic originates from multiple clients simultaneously, making it impossible to stop by simply blocking a single source. High Installation and Management Costs Hardware Investment Server machines must be significantly more powerful than standard client machines, resulting in high purchasing costs. Personnel Expertise Managing complex server networks requires hiring skilled employees with deep infrastructure and networking knowledge.