The advantages of using thin clients are numerous. Thin client usage results in lower administrative costs and greater security. Since all processing occurs on a server and is centrally managed, the local environment is stateless and the hardware has fewer points of contact with processing activity resulting in a lower probability of error.
In stateless environments software programs do not retain data or configuration settings between processes. The World Wide Web that uses HTTP (Hypertext Transfer Protocol) is the most dominating stateless environment. Once a process is completed and a web page is delivered, the connection is closed. Cookies help counter this.
Stateless environments also protect against malware, which is software designed to damage a system without the user’s consent or knowledge. They are essentially the same thing as viruses, but can include worms and spyware, to name just a few examples. Thin clients are protected against malware since no application data exists on the server; it is all centrally managed on the server. Thin clients also reduce hardware costs by not requiring disks or supporting application memory. They also don’t require updating as regularly or become obsolete as quickly. Hardware is also better utilized in thin clients. Thin clients can share memory, while CPUs (Central Processing Units) remain idle. Several users can run the same program simultaneously, but the program only needs to be loaded once with a central server.
Meanwhile, in fat or thick clients, each workstation must contain a copy of the program to run it. Thin client servers use less bandwidth, which also reduces costs. Since most terminal servers exist on the same network as file servers, network traffic mostly occurs in the server. Thin clients use resources more efficiently. They only use the minimal resources to accomplish a requested task. Finally, thin clients make it easy to add resources, as they are needed. Thin clients make upgrading easier and more efficient as well.
The disadvantages of thin clients can also be understood as the advantages of thick/fat clients. For example, thin client servers require a high performance level, since this is where the bulk of processing takes place. In contrast, thick clients perform much of their own processing on their end before sending it to servers. Therefore, thin clients make servers expensive and complicated.
Thin clients do not support multimedia-rich applications, like video gaming. Multimedia-rich applications require a significant amount of bandwidth to function to their maximum potential. Thin clients’ use of relatively little bandwidth mean that animation; video, and other graphic features are not well supported in this environment. For example, thin clients are often overwhelmed and stop working when they are required to stream media or use Flash players.
Operating systems like Windows are designed to run on local resources. This actually makes them less flexible, in direct contradiction to it proposed goals. Since thin clients run on remote resources it may be difficult to run these systems on thin client-server networks. High latency networks, where the lag time in transferring data over a network is long, can make thin clients unusable. If a network is down, there is no way for a thin client to access the server and processing power it needs to respond to requests. In contrast, thick clients can continue to work offline if a network is down. This single point of failure means that thin clients are prevented from using and desktop applications and may result in lost work.
Thick clients also allow background data transfer while working on other tasks using local resources. Thin clients also make it difficult to track individual user behavior, which is often analyzed to provide more customized responses to frequently asked requests and predict future user behavior for more efficient use of resources. Finally, thin clients create server-side bottleneck and scalability issues. Scalability refers to a system’s capacity to scale or provide processing power according to data volume. When not using think clients, desktop applications scale automatically and each new client added to a network add processing power. Thin clients only place more demands on the server and the network as they increase in number. Once the workload threshold has been crossed, server architecture must change and potentially increase. These changes are costly and often occur after serious crashes.
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