Glossary
What is a client-server network? | ExpressVPN Glossary

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Client-server network

What is a client-server network?

A client-server network is a network architecture in which clients make requests for services or information and servers respond to those requests. This is one of the two main network models; the other is peer-to-peer (P2P).

How a client-server network works

Diagram of the flow of a client-server network from the client device to the server and back to the client. A typical client-server network interaction follows this simple two-step format:

The client sends a request for data or services to the server.
The server validates, processes, and responds to the request.

The server manages access permissions and serves as a centralized data repository. Network protocols, such as Hypertext Transfer Protocol (HTTP), File Transfer Protocol (FTP), and Simple Mail Transfer Protocol (SMTP), enable communication between clients and servers.

Security controls, like firewalls and passwords, are typically in place to protect the server’s resources, and the system scales well by adding clients or upgrading/adding servers as needed.

Examples of client-server networks

Well-known examples of client-server networks include websites (browsers act as clients, with web servers as the servers), email services, corporate file servers, cloud-based applications, and multiplayer gaming servers.

Advantages of client-server networks

Centralized data management.
Stronger security compared to P2P networks.
Easier backups, recovery, and updates.
Scalable infrastructure.
Reliable resource sharing.

Disadvantages and limitations

Server issues can affect all clients.
Powerful and expensive hardware requirements.
Risk of network congestion due to high numbers of clients and requests.
Requires dedicated admin effort for maintenance, updates, and monitoring.

Client-server vs. peer-to-peer

Model	Client-server	Peer-to-peer
Storage and management	Centralized	Decentralized
Best for	Organizations and cloud systems	Small networks and file sharing
Cost	Higher, due to the need for dedicated servers	Lower; no dedicated servers are needed
Stability	Higher and more predictable (with redundancy and proper hardware)	Generally lower (depends on peers staying online; resilient to single failures but prone to disruption from churn)

Security considerations

To maximize security on client-server networks, it’s important for servers to have strong authentication systems and firewalls to filter incoming requests. Data encryption and smart access controls also help to protect client-server communications, while regular updates to client devices and servers can reduce vulnerabilities.

FAQ

Is the internet a client-server network?

Yes, the internet largely relies on the client-server model to operate, with devices (clients) requesting information from servers, such as webpages, emails, and media. At the same time, certain parts of the internet operate on a peer-to-peer (P2P) model, such as with certain file-sharing systems and voice over internet protocol (VoIP) platforms.

What is an example of a client-server application?

Web browsing is a well-known example of a client-server application. The browser serves as the client, requesting website data from web servers, which respond by sending webpage content back to the client devices.

Why do businesses use client-server networks?

Businesses generally rely on client-server networks for efficiency, centralized control, scalability, and the ability to centrally manage security features such as permissions and policies. This helps protect sensitive business data and supports compliance.

Is client-server more secure than peer-to-peer (P2P)?

Generally, yes, client-server networks are more secure than P2P because security is centralized and managed by administrators. This allows admins to set up firewalls, implement security policies, and control access, whereas P2P networks rely on individual users to secure their own nodes, which can lead to inconsistent data protection and increased vulnerability risk.

Can home networks use client-server models?

Yes, home networks can and do use the client-server model for certain services, such as printing or media streaming. At the same time, most local device communications, such as file sharing between PCs, follow a peer-to-peer (P2P) model instead.