What Is Client-Server Architecture?

Key takeaways

Client-server architecture is a type of network pattern in which multiple devices connect to and access data stored in a centralized server.

• Client-server architecture follows a request-response protocol, where the client or user requests data, and the server provides it.

• Typical components of a client-server architecture include clients that send the request, servers that store and process data, and networking devices that connect the clients and servers.

• You can use client-server architecture for sending and receiving emails, hosting websites, supporting cloud structures, and accessing applications on the internet. 

Explore the function of a client-server architecture, including its various tiers, components, and characteristics. If you’re ready to start building expertise in IT networking concepts, enroll in the IBM IT Support Professional Certificate. You’ll have the opportunity to learn more about foundational IT concepts like cloud computing, networking, and databases in as little as three months. Upon completion, you’ll have earned a career certificate for your resume.

What is client-server architecture with examples?

Client-server architecture refers to a network where many devices connect to a centralized server, allowing users to access different stored data and perform diverse tasks simultaneously. The client refers to the person or device requesting information, and the server refers to the device that provides this information. Client-server architecture follows a protocol known as request-response, which means the client requests information or data, and then the server provides the requested data. This pattern involves specific rules, guidelines, and languages to ensure it’s standardized across different types of servers. It provides a seamless user experience, regardless of the user's device, for connecting to the server. 

For example, the client might visit a website. When that person enters the URL they want to see, the server requests and displays the website domain. Other operations operate similarly. When you send an email, you essentially request that the email server transmit your email to the intended recipient. This format also enables more advanced security measures. If you send a request that goes against what the server allows, the server can reject your request.

Read more: A Guide to Database Server Certifications

Characteristics of client-server computing architecture

While you can have different styles of client-server architecture, many have similar core features. Common characteristics you might see include:

• The architecture uses a request-response pattern while following the requisite rules and protocols.

• The architecture has vertical and horizontal scalability. The network can easily add or remove servers (vertical scaling) or user workstations (horizontal scaling) without compromising functionality. 

• Multiple devices or workstations connect to one central server simultaneously, accessing the same resources if needed.

• Servers typically provide services such as file storage and sharing, as well as printer and application access.

• The architecture uses a network protocol to make it easy for devices to communicate quickly and efficiently.

Types and tiers of client-server architecture

Professionals sort client-server architecture by the types of requests and tasks the system can handle. These tiers of client-server architecture include the following:

1-tier client-server architecture

Tier one architecture is an all-in-one architecture. It stores all the information required for the server to function inside one package. These settings often include the user interface, database logic, business logic, and database settings as one layer on a shared drive. Smaller networks, for example, typically rely on tier one architecture.

2-tier client-server architecture

Two-tier architecture breaks the user interface and database into separate servers and layers, allowing clients to make outside requests. Like online reservation systems, this architecture is popular for sending and retrieving contract information.

Think of this like ordering at a coffee shop. You (the user) tell the barista (database server) your order, and they make your drink to your specifications. While this is effective with a small volume of traffic in the coffee shop, it may cause delays if you have a long line of customers with complex orders.

3-tier client-server architecture

Three-tier architecture introduces middleware into the client-server architecture. The middleware offers better security and the opportunity to handle more complex tasks and requests. The layers are divided into a presentation layer, a database layer, and an application layer.

Continuing the coffee shop example, you can think of this as placing your order (user request) with a cashier (application layer), who then gives your order to the baristas (database server) to make the drink. Given the higher number of customers, dividing tasks and creating a more streamlined system to receive orders and provide drinks becomes essential.

N-tier client-server architecture

N-tier architecture adds additional middleware layers to create more complex client-server systems that handle more varied types of network traffic and tasks. This client-server architecture is desirable for any organization because it is flexible and scalable. 

In an N-tiered coffee shop, you would see several layers of cashiers, waitpersons, baristas, and even shop managers who work together to take orders, collect ingredients, prepare drinks, and deliver coffee to customers.

Major components of client-server system architecture

Client-server architectures typically consist of the following major components:

• Clients: Also known as server requesters, clients can be personal computers, workstations, or other smart devices that send requests to the servers and then receive the information.

• Servers: Servers are large devices used to store and process files, databases, and programs. You can work with several types of servers, such as application servers, database servers, web servers, and computing servers.

• Networking devices: These devices connect workstations and servers and allow them to communicate and send information effectively. Examples of networking devices include hubs, bridges, switches, gateways, and routers.

Is MVC a client-server architecture?

No, the model-view-controller (MVC) pattern is a separate type of software architecture. In MVC, the model acts like the business layer, controlling data and business logic. The view component handles data display and user interactions. Finally, the controller acts as a bridge between the model and view components, processing user requests to generate appropriate outputs.

Examples of client-server architecture

Businesses use client-server architecture to facilitate professional and casual interactions between clients and servers. Some examples of when you might use client-server architecture include:

• Email server: Client-server architecture facilitates the sending and receiving of emails.

• Domain name system (DNS) server: This type of client-server architecture hosts websites and allows users to access them daily.

• File servers: This client-server architecture supports structures like the cloud, where users store and interact with documents, spreadsheets, presentations, videos, and more.

• Application servers: These servers allow you to access applications on the internet without downloading a copy of the application to your device.

Pros and cons of client-server architecture

Client-server architecture has many benefits for business networking. One is the ease of managing it because one single server hosts the needed files. Another is that it allows different platforms to share resources, making accessing and sharing important information more efficient. 

Because the servers are scalable, a business can tailor its architecture to match its size, growth, and needs. This type of structure is key to creating easily usable interfaces that provide clients with the needed information, regardless of company size. As the organization grows, the server size can seamlessly expand without disrupting current usage.

However, client-server architecture also has drawbacks, which are essential to consider when choosing the proper structure for your needs. Because servers run continually, they require constant management and maintenance, including updates and network troubleshooting. Servers also run hot, so they often require a separate room for storage. Both of these things can be expensive over time. 

In addition to maintenance and storage, if too many users try to request data at once, the network becomes congested and runs more slowly. Large businesses should consider this risk, especially when accessing time-sensitive information. Organizations should invest in the server architecture required for their company size and manage server usage to minimize this risk.

Navigate your career journey with confidence

Thinking about building new strengths? Explore in-demand skills and the latest trends in your industry by joining our LinkedIn newsletter, Career Chat! Or if you want to learn more about concepts, careers, and courses related to IT, check out these free resources:

• Take the quiz: Which IT Course Should You Take? Find Out in One Minute 

• Watch on YouTube: How to Become an IT Professional 

• Bookmark for later: Information Technology (IT) Terms: A to Z Glossary 

Accelerate your career growth with a Coursera Plus subscription. When you enroll in either the monthly or annual option, you’ll get access to over 10,000 courses. 

Build job-ready skills with Coursera Plus

Start 7-day free trial

• 
• 
• 
• 

Start 7-day free trial