Thin client and VDI: what they are and when they’re worth it

Thin clients and VDI move employees’ computers onto the server: only simple terminals stay in the office, while applications and data run centrally. The solution pays off especially for companies with many similar workstations.

What is a thin client?

A “thin client” is simply a very basic device used to run applications and access data on the server, without a computer in the traditional sense of the word. You use it like a computer, but it’s really just a terminal, usually with no fan and no data drive, that handles access to the data and applications on the central server. The monitor, keyboard and mouse plug into it.

What is VDI?

VDI (Virtual Desktop Infrastructure) means desktop virtualization: each user has a Windows desktop running in a virtual machine on the server, and the terminal only displays and controls it. The simpler option is shared sessions on an application server, for example Microsoft’s Remote Desktop Services (RDS), formerly Terminal Services: several users work on the same server, each in their own session.

We’ve also written about virtualization in general in the article IT made simple: virtualization and cloud computing.

What desktop virtualization solutions are available now?

• Microsoft Remote Desktop Services (RDS), included in Windows Server, with separate access licenses for each user or device;
• Citrix, with its Virtual Apps and Desktops solutions;
• Omnissa Horizon, formerly VMware Horizon: the VMware division that develops it became the independent company Omnissa in July 2024;
• Azure Virtual Desktop and Windows 365, from Microsoft, where desktops run in the cloud, with no server in the office. We wrote about Windows 365 in the article Windows 365, or how to have your own computer in the cloud.

What are the advantages of thin client terminals?

• lower management costs: data and applications live only on the server, and updates are done there, just once;
• they use much less power than a regular computer;
• all workstations can be monitored from a central point, and users can’t install programs locally;
• installation, relocation and servicing take minimal time: no local settings are needed, and a faulty terminal is quickly replaced;
• data stays on the server, not on the workstations: a lost or stolen terminal doesn’t expose company files, and unauthorized people have no access to applications;
• the workstations have no data drives, so there’s less risk of a virus getting into the system through them; protecting the server is still a must, though;
• they rarely freeze, because they don’t run applications locally and don’t need many resources;
• hardware upgrades are done only on the server;
• they use passive cooling, which lets them run trouble-free for a long time, without any noise;
• users’ open sessions are kept on the server even during a power outage that affects the terminals, provided the server is connected to a UPS: when the power comes back, users pick up their session exactly where they left off.

What are the drawbacks of a thin client system?

• if the server or the network goes down, nobody can work, so the server needs redundancy, a UPS and backup;
• licenses don’t go away: besides the server license, access for each user or device is paid for separately, and Windows virtual desktops need licenses specific to virtualization. Linux terminals don’t need their own Windows license, but access to the Windows applications on the server is still licensed;
• video calls, graphics applications and design work (CAD) require special configurations or servers with graphics cards;
• for cloud desktops, the office internet connection has to be good and stable;
• for just a few users, a virtualization server can cost more than a few well-managed laptops.

When are thin clients and VDI worth it?

When the company has many similar workstations and wants to manage them from one place: call centers, service counters and front desks, offices that work in shifts, branch locations in other cities, or companies with sensitive data that mustn’t end up on employees’ computers. VDI also helps with working from home: employees connect to their desktop from any computer, and the data stays on the server.

For developers, designers or anyone who needs a lot of computing power and graphics applications, traditional desktops or laptops usually remain the better option. We explain the differences between an office server and a cloud server in the article on local server vs. cloud server.

The bottom line: the company buys a server powerful enough to support all the “PCs” in the company, or rents the capacity it needs in the cloud, plus the necessary software licenses and thin client terminals for users, along with a monitor, keyboard and mouse.

And end users get an experience similar to the traditional one, but without an actual computer in the office, and without its noise.

RezolvIT designs and manages IT infrastructure for companies of any size, from offices with a few computers to the Romanian subsidiaries of multinationals, with servers in the office or in the cloud. If you’re not sure which option suits you, ask for a free IT audit.