Thin Client Advantage
Eric Aasted · T.H.E. Journal Technological Horizons in Education · 2001
What is a Thin Client Computing Environment? A thin client is similar to the traditional host client computing environment, except a thin client computer has a minimal hardware set; most of the computational load is executed on the host computer, and the host also provides space for applications and files. The thin client should have a low power, high performance CPU with good graphics. They do not require spindled drives, such as a hard drive, floppy drive, CD-ROM drive or DVD drive. The power required for a thin client is readily available by use of a small modular power supply. These simplifications result in a very small footprint. Many of the present generation of thin clients are built within the display device, or externally mounted behind or beneath a fiat panel or CRT. The operating system of the thin client may be onboard the thin client in flash memory or other programmable memory. Typical operating systems are WinCE and Linux. In addition, some browser applications may be available. Having a resident browser shifts the computation load ratio from the host to the client. This is acceptable, as long as the client has flash or similar nonvolatile memory to maintain user settings, bookmarks, cache, etc. Where Thin Clients Work Best Thin clients do not rely on local fast processing. For almost 20 years, hallway discussions in schools have revolved around who had the newest, fastest computer with the biggest hard drive and the biggest display screen. Newer operating systems have always required more speed, bigger disk drives, and more RAM. However, in the past few years, more and more applications do not show any apparent speed increase when you get that faster, more expensive processor. More mundane things, like hard drive access time or Ethernet access, limit apparent response speed. At the same time, many schools are sharing project and department data using servers. So, the local hard drive size is not as important. The local hard drive only has to support local applications. In the thin client computing environment, the applications are moved to the server. Modern servers are very fast, and are typically operating at 1 GHz or faster. Because the enterprise data and applications are local to each other on the server, many times the user will find that the thin client environment appears faster than having the data local. The thin client is primarily a high-end display device with a keyboard and mouse. The thin client computing architecture is similar to computing configurations from the 1960s and 1970s. The host computer is larger and more expensive than the client computer, which is mostly intended for display and data input. Computing shifted away from that architecture in the 1980s because of low server reliability and high maintenance costs. Servers are now very reliable, and are often taken for granted. They are presumed to be always available. For instance, most e-mail systems normally store e-mail data on the server. Only if the e-mail application is specially configured does the e-mail data get downloaded to the client. The modern thin client user experience is configured to be similar or identical to the experience a typical user would have with a full-featured desktop computer running Windows 2000 or something similar. The speed and workload of the host server determine the actual user experience. For most users, an acceptable ratio is about 30 to 60 thin clients to one host server. When a software or hardware upgrade is required, only the server needs to be upgraded. Normally, the upgrades can be done during evening or weekend hours. Because all thin clients run from the same server, they naturally are all at the same application revision. With upgrades occurring on only one machine, the server, most upgrades can be made in a few hours. Schools are one of the most popular environments for thin client, as most classrooms have 15 to 30 pupils. Several states and some countries are preparing to modernize their school computer resources now or in the near future with thin clients. …