Thin Is In
11/15/2005 By: Matt Villano
Despite soaring obesity rates, Americans know all about slimming down. Walk through any supermarket today and you'll see products geared for the South Beach Diet, the Atkins Diet, and a variety of no-carb, low-carb, and all-carb diets in between. What's true for eating habits is true for technology, as well. Across the country, an increasing number of school districts are discovering that thin client technology can be just as good as traditional desktops at handling computing needs.
1. What is thin client technology?
The idea behind thin client computing is simple: to distribute computing power by centralizing it on an application server connected to the network while providing users with inexpensive "client" devices that are easy to install, upgrade, and maintain. These thin clients are slimmed-down versions of traditional computers — each offers basic programs and a bridge to functions and applications stored on the server. All thin client models work seamlessly with current computing infrastructures and computing standards as well as with all Windows-based applications. (Note: Apple offers Web Objects software for emulating thin clients in Mac OS X environments.)
2. How many different types of thin clients are there?
There are two basic types of thin clients: those that come as hardware designed to replace traditional "fat client" computers and those that come as software or a service designed to be used on traditional desktops. Depending on the vendor, most thin client units cost about $400 each, not including the monitor, a keyboard, and a mouse.
Thin client hardware devices are about the size of small textbooks. They contain fewer parts: a microprocessor capable of processing graphics, network interface capability, a video subsystem, and enough memory (about 9 MB) to run software that connects to the server. They include ports for Ethernet, monitors, and printers, but they lack hard drives, floppy drives, and CD-ROM drives. A sealed case design prevents users from tampering with the device.
Thin client technology also comes in the form of software or services that customers can purchase and configure to work on older desktops. The software model, made famous by Citrix with its MetaFrame Presentation Server 3.0 Independent Computing Architecture, locks down functions users don't need, thus controlling and centralizing the amount of available computing resources during a user session. Vendors who specialize in thin client software packages include Sun, Neoware, and Novell.
K-12 customers can purchase licenses for this software, or they can subscribe to a variety of software applications and educational content through a third-party application service provider (ASP). In the latter, the ASP owns and maintains server equipment across the board. When it's time to upgrade the software, the ASP handles everything.
3. What are the benefits?
Because the bulk of thin client applications reside in a central spot on a server, the technology has the potential to enhance network management. Network managers can configure everything remotely, setting protocols, handling maintenance, and troubleshooting problems for the network with the click of a mouse. For example, a simple change to correct the spelling of a menu item is done at one place on the server, and all users see the change the next time they log on. What's more, because software applications are updated at the server level, upgrades are quick and painless.
Some additional advantages:
- While most PCs take two to three minutes to launch an operating system and access the network, thin client computers generally boot up and access the server in less than 30 seconds.
- Thin client computers display data more rapidly than PCs: because all processing is done on the server, no database information goes back and forth over the network, a process that typically slows computing processes to a crawl.
- Thin client devices free up valuable desk space.
- In terms of energy consumption, recent statistics indicate that thin-client computers use one-sixth the power of traditional desktops, which could save large districts thousands of dollars on utilities.
- Thin clients require backup only at the server site, eliminating the costs and redundancies normally associated with local data backup on traditional PCs.
- Thin clients improve security. The lack of hard drives and disk drives mean it's almost impossible for users to upload or download viruses or other security threats.
- Unlike PCs, thin clients are not targets for theft because they are useless unless they are connected to the proper server.
According to a National Semiconductor report, by eliminating continuous repair cycles, easing software/hardware upgrades, expediting processing power, and improving security, thin clients can reduce organizational costs by 25 to 40 percent. For school districts with limited budgets, that means monumental savings.
4. What are the downsides?
While thin-client computing offers many benefits, the technology is far from perfect. For starters, no hard drives means users must save their work on the server or e-mail it to themselves for later access. Second, because many thin client devices lack CD-ROM drives and USB ports, educators can't use CD-based software, digital cameras, and other gadgets with the technology. Another problem is the issue of compatibility — not every piece of education software will run in a thin-client environment.
Perhaps the most significant drawback to the thin client approach is network reliability. Because thin clients require constant connectivity with the servers they are accessing, systems require substantial bandwidth to support all of the communications being transmitted over the network at one time. Districts considering thin clients should therefore possess the bandwidth and servers they need to process a typical load. Most standard K-12 thin client environments include two or three servers on the back end to address this issue. In larger school districts, technologists have been known to purchase six or seven servers to be safe.
5. Can thin clients be used in wireless environments?
Several recent developments are fueling interest in wireless thin clients. One is the growing use of operating systems tailored for thin-client devices, including Windows XP Embedded and variants of Linux. The core middleware components of a wireless thin client deployment are essentially the same as those used in conventional thin client desktops. The difference is that they connect back to the server wirelessly, and therefore require additional security measures to encrypt the transmission.
Districts wanting to deploy thin clients in a wireless environment may want to consider augmenting their wireless local area network (WLAN) to support increased bandwidth demands. Among those districts that have had thin clients for years, 56k dial-up connections have proven shaky at best. Generally, WLANs that support wireless Voice over Internet Protocol can support thin client connections. In districts that suffer from the limited bandwidth of a cellular network, additional WLAN antennas may be necessary.
6. What else should I consider?
Comprehensive training is paramount. Users must understand the benefits and shortcomings of the technology and how to alter user behavior to eliminate reliance on a local hard drive. Users also must be taught to log off after every session: thin client devices receive updates only in between user sessions, so sessions that extend for days and weeks could delay upgrades and impede system performance. The most effective way to train users is to start with district-level users and then move to building-level educators. Once teachers are familiar with the technology, they can pass along nuances to students.
Matt Villano is a California-based freelance writer who specializes in educational technology.
- Survey your district's computing resources in order to decide between hardware and software/ services approaches to thin client computing.
- Consider thin client devices that offer USB ports if your district relies heavily on peripherals.
- Before you invest in thin client computing, make sure your district has ample bandwidth and server power to meet user needs.
- Be aware that thin client technology works wirelessly, provided you have a wireless network sophisticated enough to support it.