Thin servers?a.k.a. server appliances or ultradense servers?won’t boldly go where larger, traditional servers cannot (unless you count exceptionally small closets). They do essentially the same things as their larger brethren. But instead of trying to be all things to all users, thin servers support a single activity simply, reliably and inexpensively. According to Pushan Rinnen, an analyst with Stamford, Conn.-based research company Dataquest, these features will help the server appliance market experience 62 percent compound annual growth rate from 1999 (slightly under $1 billion) to 2004 (more than $10.5 billion).

Doing One Thing Well

Common server appliances provide a straightforward solution to a standard server function?printing, Web serving, e-mail, file sharing and such. They are usually bare-bones devices costing less than $2,000 and designed to fit in single-space, rack-mounted cases the size of your average pizza box. Installation generally involves plugging them in, turning them on and configuring a few settings through a simple browser-based interface. Once configured, they can be pretty much left alone to do their jobs with minimal intervention. And if one goes down, you simply pop another of the devices into its place.

Appliances also have another appeal, says Giga Information Group analyst Stacey Quandt in Santa Clara, Calif. Companies can purchase the appliances as needed, and they cost relatively little compared with most traditional servers. As a result, enterprises can realize return on investment in months rather than years.

That said, there are significant drawbacks to the thin server model. The de-vices are usually designed to do one thing and one thing only. If you suddenly need more firewall protection and less Web serving, you can’t reconfigure your existing thin servers to perform the necessary tasks. And today’s servers often use mobile processor technology and less expensive (nonerror correcting) RAM to reduce costs and keep power consumption low, but such components don’t have long histories of reliability in the server space. Given those caveats, companies must be careful about where they incorporate the devices.

Despite the question marks, many big-name computer vendors, such as Compaq, Dell and IBM, have begun jumping into the thin server market along with small makers, the likes of Los Gatos, Calif.-based FiberCycle Networks; Rebel.com in Ottawa, Canada; and RLX Technologies in The Woodlands, Texas. The power of the lure to thin servers is evident: Compaq even filed suit against startup RLX, alleging that the new company stole away key high-density server developers from Compaq projects.