What is a thick client?

A thick client is a powerful computer on which a full-fledged operating system is installed. Its char­ac­ter­ist­ic feature is its per­form­ance. It has suf­fi­cient capacity for local work and the in­de­pend­ent execution of tasks. An example of a thick client is a desktop PC on which Windows is installed as the operating system.

Defin­i­tion and char­ac­ter­ist­ics of a thick client

A thick client is a type of client that has its own computing power, storage media, and graphics resources. With these dedicated computing resources, thick clients are able to run programs locally and in­de­pend­ently of server resources. In most cases, it also means that users have access to rich graphical user in­ter­faces. Thick clients are commonly referred to as fat clients.

There are several char­ac­ter­ist­ics that make up thick clients. Data pro­cessing, output, and input take place locally on the client. Data storage takes place on local memory resources. If a fat client is connected to a network, data storage can also be performed on a storage medium in the network.

A fat client has all the pre­requis­ites for accessing a network’s services. By being equipped with many in­ter­faces, the client es­tab­lishes con­nec­tions to storage drives and peri­pher­al devices, like printers.

On one hand, thick clients can be used on their own. On the other hand, they can be used in com­bin­a­tion with a server. In this way, in­di­vidu­al tasks or ap­plic­a­tions can be out­sourced to the server.

What are the ad­vant­ages of a thick client?

Using thick clients has several ad­vant­ages. They can be used in­di­vidu­ally as a stan­dalone resource. In addition, no direct con­nec­tion to a network is required for full func­tion­al­ity. This means that their self-suf­fi­ciency enables offline work.

If a thick client is used in com­bin­a­tion with a server, the demands on the server in terms of resources are lower, since the fat client runs the programs locally using its own resources.

Complex mul­ti­me­dia ap­plic­a­tions in the mul­ti­me­dia area, like rendering graphics, run in­de­pend­ently of internet con­nec­tion and bandwidth due to local execution. When trans­fer­ring the task to a server, high bandwidth re­quire­ments follow. Due to the thick clients’ own high computing power, the server in the client-server model can serve multiple clients sim­ul­tan­eously. In general, the fat client is con­sidered a versatile client that can run many different ap­plic­a­tions sim­ul­tan­eously.

What are the dis­ad­vant­ages of a thick client?

While thick clients have many ad­vant­ages, they also come with some dis­ad­vant­ages. The ad­min­is­tra­tion of fat clients is much more complex since the operating system and programs are installed locally.

The complex ad­min­is­tra­tion makes it more difficult to secure the system. Securing each in­di­vidu­al client against cy­ber­at­tacks is a costly and resource-intensive process. Ensuring cy­ber­se­cur­ity is a factor that should not be un­der­es­tim­ated when working with a fat client. The bundling of resources makes the system vul­ner­able. If malware is de­lib­er­ately installed by malicious code, there’s a risk of the system failing al­to­geth­er. This could, for example, occur when opening a con­tam­in­ated email at­tach­ment.

Since thick clients are equipped with a lot of hardware, they are expensive to procure. Since the hardware consumes a lot of power, they’re also energy-intensive to operate.

What can thick clients be used for?

There are many possible uses for thick clients. In the corporate context, fat clients can function as work­sta­tions. The creation of CAD models, pro­gram­ming software, or the work­sta­tion of a sales employee are common scenarios. Thick clients can also be used for different kinds of content pro­duc­tion, like the creation of videos for video marketing purposes.

In the private sector, fat clients also have a variety of uses, es­pe­cially when it comes to gaming. Many users also use thick clients to manage and store personal files and data. Here, however, more and more users are switching from local storage to cloud storage. This allows users to access their files and data from different devices.

What’s the dif­fer­ence between a fat client, thin client and zero client?

In addition to the fat clients, there are other clients in the client-server model, namely the zero client and thin client. The table below explains how they differ in terms of features and char­ac­ter­ist­ics.