Focus: Thin Client

Several years ago, I clearly remember hearing for the first time about thin client computing, and that Microsoft was planning to support this “new” computing environment. Like many engineers, I was skeptical at first, but having taken the time to learn about what thin client computing is and is not, I now think it is the only practical solution to many of the problems that educational institutions are facing worldwide. As a technical manager in a large, high tech company, I was invited by my department manager to participate in discussions on how to reduce the churn the department was experiencing from the continual treadmill of upgrading hardware one year and operating systems and applications the next year. There seemed to be constant pressure to upgrade hardware and software from internal sources. The yearly cost to replace even 1/3 of our computing hardware was staggering, and something had to be done.

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 flat 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 d'es 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. For thin client at school, the teacher operates the host computer, while the students operate the thin client computers. The teacher has the option of having students’ computers display the host computer screen during lectures, allowing each student to do his or her class work independently. The teacher has complete flexibility and control over thin client activities.

Thin-Client User Advantage

Most users, when asked about their computer experience, will tell you they use their computer all the time, but they are actually typing in a word processor program, or reading e-mail. These are not compute-intensive applications. What the user is trying to say is that he or she needs access to his or her computer all the time. Thin clients tend to make more computers available to everyone all the time. With thin clients being much less expensive on a per-seat basis, more seats can be made available. Since servers usually use large hard drives, the user hard drive space appears to be virtually infinite, and enterprise data can be backed up easily. Most thin clients are well able to run large screens, up to 1600 x 1200 pixels, and the nicer models are packaged with the very desirable flat panel displays.

In addition, the thin client computing environment is much more secure. Because there are no removable drives, students cannot run foreign disks that may have a virus. A thin client desktop deployment survey conducted in 2000 by the Gartner Group summarizes that “users moving from PCs to Windows terminals will have access to the same applications. The PC has become a network appliance. Many PC users hardly ever use the diskette or CD-ROM drives because their information needs are met via the network.” Survey respondents tended to like “Windows terminals because they don’t have to reboot constantly, they have access to the latest versions of software and to the Internet, and because performance is not noticeably different.”

Thin Client Growth Advantage

Thin client computing is expanding at a very high rate. Forecasted growth shows 700K units/year in 1999 growing to 10 M units/year in 2004. According to the 2000 Enterprise Thin Client Market Half-Year Update, thin client expansion rate is expected to accelerate due to the availability of Windows 2000 with built in thin client hosting capabilities. National Semiconductor is one of the leading suppliers of thin client silicon solutions today. Leading original equipment manufacturers include Wyse, Compaq, IBM, Boundless and many others. Original plans for thin client computing anticipated a hardwire Local Area Network (LAN) running at 10 Mbps or 100 Mbps. However, new network components are now available, and will be installed soon operating at 1,000 Mbps. Thin client computing is expected to virtually explode in the next few years.

Thin-Client Cost Advantage

Many considering the cost of deployment will look at the initial hardware and software configuration. However, the total cost of ownership (TOC) over the product lifetime is much more important. Thin client hardware cost is only about 1/2 of the hardware cost for a full desktop configuration, and thin client software on the client side is essentially fixed. The thin client software for the host is part of Windows 2000. However, a National Semiconductor study shows that the company went from a TOC of $7,600 per seat to $3,250 per seat. System-wide savings for 7,400 employees have been estimated at $30 million per year. IT support reduction is over 80%. Typical ratios for IT support are on the order of 100 to 1 for PC based networks, and 500 to 1 for thin client based networks. Other IT functions, such as password creation, training, debugging, and server backups, will remain constant, or have minimal reduction. The same can hold true for schools and districts.

Another strong case for thin client computing is rapid, system wide application or operating system upgrades. Since applications are stored on centralized “farms,” many schools can upgrade all thin client servers within four hours or less. This sort of rapid, system wide upgrading is commonly reported. In the past, as in my own experience, PC-based networks that require upgrades on an individual basis can lead to an IT staff that is dedicated to nothing more than performing quarterly upgrades. This means all the enterprise machines are running slightly different versions of applications or operating systems, as the enterprise is incrementally upgraded.

Conclusion

Thin client computing has several key advantages over the present desktop computer with server environment of today. Most importantly, thin clients are no longer just an idea; they are a reality with increasing possibilities that are installed by big names in the computer industry. Thin clients offer key advantages for the user, for the information technology group, and for the corporation to stay current with a significant reduction in lifecycle costs.

Eric Aasted
Leader, Engineering Program
Management Group
National Semiconductor, Inc.

National Semiconductor provides system-on-a-chip solutions for education. Their chips are used in 80% of all thin client systems. The Thin Client@School initiative demonstrates optimal thin client solutions for K-12 education settings. National Semiconductor has partnered with technology companies and integrators to support pilot projects in the U.S., Germany, China and other countries. For more information, visit www.national.com/thinclient@school.

Contact Information
National Semiconductor, Inc.
Santa Clara, CA
(408) 721-5000
www.national.com

This article originally appeared in the 06/01/2001 issue of THE Journal.

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