by Andrew Starling

Enterprise Appliance (Thin Client)

Strange how quickly things come full circle, especially in the IT world. Here we are once again with the dumb terminal idea, bouncing back from the old mainframe days, with a few new features to bring it up to date.
December 14, 1999

Fortunately Sun Microsystems has put enough new twists into this old idea to make it a real contender. Take the Sun Ray seriously. It's a future champion.

Top of the twist list is Hot Desk, a new concept that lets you jump from machine to machine within a workgroup and pick up where you left off. Simply insert your personal smartcard into any Sun Ray on the network and you're back exactly where you were before, with the same screen, files and applications open. It's instant and works perfectly. It doesn't matter where you are in the office, the terminal you put your smartcard into is yours.

Then there's the fully centralised control. Before the Internet and smart viruses came along, it wasn't too worrying if network users loaded a game or two on their hard drives. Things have moved on, and right now it's relatively easy for somebody to accidentally kill an entire network by opening the wrong email attachment.

The Sun Ray system shifts the responsibility for security from casual users to the system administrator. If the server is set up securely, nobody on the network can do much harm. There are no floppy drives, no individual security settings, and no options to open files the system believes are unsafe.

To set the system up, a Solaris server is loaded with Sun Ray Enterprise software and user applications. Up to 30 Sun Ray appliances are then attached via 100 Mbps fast Ethernet. It doesn't take long to configure the system. The set up we tested was put together by Systems Manager Dave McNeill at Carlton Online, London. Dave said "It's pretty easy to set up. It took me about an hour."

"I find the Hot Desk concept interesting, and I can see the advantages for network administrators. For example there's no updating at individual machines. Everything's centralised."

Each individual appliance is connected to a screen, and through USB ports to a mouse and keyboard. There are two more USB ports spare, but they're not especially useful since peripherals such as printers and scanners only run from the server, not the individual appliances. Sun says it's planning changes in mid-2000 that will bring the extra ports into play.

The physical appearance of the appliances is unusual. Something like a closed laptop inserted into a triangular toaster. Very modernistic. Each includes a smart card reader for hot desking, but no floppy drive. There's very little processing power in the appliance. Even the screen frames come down the interconnect and aren't created locally.

Users who aren't familiar with UNIX might need some training, but it is possible to put familiar Windows applications on the system. Sun's recent acquisition of StarOffice has allowed it to include basic Windows capabilities free of charge. Full NT applications are available through the Citrix ICA client for Solaris and a Windows NT Terminal Server running Citrix Metaframe.

Although the centralised control would be an asset in many circumstances, Dave was concerned that many users wouldn't like it. "Here at Carlton we allow our users to load browser plug-ins, use ICQ and change their own cache settings. I don't think they'd be happy with a system that interferes with that freedom."

This issue of user freedom clearly has a big influence over where the Sun Ray system can be used and where it can't. As Dave points out, most web developers wouldn't appreciate losing control over their computers.

But at the other end of the scale, there are plenty of computer users who might prefer the safety and lack of responsibility that this system offers. And certainly there are many employers who would prefer to take full control over what goes on their network. Banks and call centre administrators are obvious examples.

Network loading is another important issue. The central processing of screen frames puts a heavy load on the network. If fifteen screens are busy reformatting images in Photoshop while another fifteen are downloading streaming video from the Internet, not a lot is going to happen in a hurry.

Fortunately this level of loading is rare, but it does highlight the limitations of the system. It's not built with a room full of graphic designers or video developers in mind.

Happily, the limitations of network loading and freedom match each other in most circumstances. Heavy users generally expect more freedom. Light users are more likely to accept a loss of control. Out of the two, freedom is probably the more limiting issue.

Most computer users spend their time casually entering strings of text and accessing the Internet, and a Sun Ray system can deal with refreshing thirty screens under this kind of light usage. The set-up we tested at Carlton Online was lightly loaded and the system ran blindingly fast, including graphics rendering. Most PC user would have been astonished by the speed. That's one of the features that Sun hopes will sell the Sun Ray. If the system isn't too busy, it brings the power of the enterprise server to regular users.

It seems likely that the IT industry is destined to move towards the thin client model, and eventually these clients will run on geographically distant servers, probably under IP protocols. The Sun Ray brings this concept one step closer, as well as increasing central control and introducing the novel idea of hot desking for desktop machines.