In recent years thin client computing has been about as fashionable as bell-bottom trousers. But, according to industry analyst IDC, thin client shipments will grow tenfold between 2000 and 2005, with much of that growth happening in enterprise IT departments.
Thin clients - slimmed down desktops running server-based applications - have not been talked about for a couple of years, confirms David Friedlander, a senior analyst at Giga Information Group. "The technology was dropped after being over-hyped," he says. "The domination of Win32 applications was never seriously challenged."
However, with many boards slashing IT spending, thin client technology is becoming increasingly attractive, says Bob O'Donnell, IDC's director of device technology. "The total cost of ownership benefits of thin clients resonate more soundly in the current economic conditions, and many managers are re-evaluating their options,' he says.
Cost is certainly a major benefit of thin client technology. With the typical organisation having one administrator for every 200 PCs, thin clients can cut roll out and support costs dramatically, says Milind Govekar, a senior research analyst at Gartner Group.
"The technical needs of 80% of PC users could probably be met by thin clients, but it is likely to be seen mostly in service organisations and among knowledge workers who are less wedded to their PCs," he says. Gartner estimates that total cost of ownership could be cut by 40% for this type of user.
However, there are other upsides. "Thin client architecture is more scalable, manageable and flexible than PC-based architecture," says Stephen Yeo, European marketing director at Wyse Technologies. "Many companies are now realising that having a 2Gbyte hard drive sitting on a user's desk is overkill. Thin client can eliminate that in a snap."
Still, the thin client is looking just a little plumper these days. The purist model of a thin terminal conducting almost no local processing or storage has been abandoned in favour of a hybrid model, says Friedlander. "Sales of server-based computing technology has gone through the roof, but sales of terminals have absolutely not kept pace," he says. In other words, companies are going thin on the server, but the clients are good old "fat" PCs.
"We are seeing a lot of hybrid systems, where applications are delivered thinly, but to PCs," says Chris Wallace, a sales manager at services firm ITNet. For example, remote workers might access a thin version of custom applications or Outlook while running Microsoft Word locally.
This kind of architecture still uses server-based applications that communicate with terminals using proprietary software such as Citrix Metaframe's ICA (Independent Computing Architecture), the Java-based X technology, or Microsoft's Windows Terminal Server RDP (Remote Desktop Protocol). However, whereas once there would be a workstation running Windows Terminal or a Wyse thin terminal, now it is just as likely to be a locked-down PC, says Friedlander.
"Users took the P in PC incredibly seriously, especially in the US and the UK. There was an extremely high level of resistance to using terminals," says Friedlander. In addition, while the total cost of ownership figures of thin client are appealing, the cost of terminals is comparable to that of PCs, providing little motivation for IT departments to junk thousands of desktop systems that could simply be reconfigured.
This is an analysis that is fiercely rejected by terminal suppliers. "Our sales are increasing by 40% to 50% year-on-year," says Yeo. "That is not too bad for a market supposedly in recession."
Regardless of whether organisations are using server-based computing or true thin client systems, a key driver has been the improvement of management tools, says Paul Lavin, editorial director at UK research firm Butler Group. "When thin client launched 10 years ago, the server infrastructure wasn't there," he says. "Today, thin client and server-based computing are far easier to manage - and that is where the long-term savings come from."
Key improvements to server-based systems include the latest releases of both Microsoft's RDP and Citrix's ICA management software. While RDP 5 includes improved performance over low-bandwidth connections, Citrix ICA now supports Java and allows applications to be displayed entirely within a browser - a big benefit for companies running legacy or customised applications that could not economically be rewritten for Web access.
Terminal suppliers such as Wyse are now offering multiple embedded operating systems, including Windows XP, Windows CE and Linux. "We now bundle a terminal management package that makes it more scalable and adds features such as wake-up terminals," says Yeo.
As for the future of thin client computing, Windows now accounts for 70% of the thin client terminals sold, while Citrix makes up about 55% of server-based computing sales. Those trends are likely to continue, while sales of X technology decline.
The next growth will be in Web terminals running fully featured browsers that remotely access server-based applications, says Friedlander. "This has been slower than expected because of limitations to browser functionality, but it is where we will end up - with a blending of thin client and portals," he explains.
Pro and Cons: Thin clients
- Reduced staffing and support costs
- Reduced hardware and software maintenance
- Better version control, faster software roll-outs
- Total cost of ownership reduced by up to 40%
- Functionality of Internet browsers is often limited
- Downtime affects entire organisation
- Shift in staffing to network and server roles
- Resistance from users to give up "their" PCs
This was first published in March 2002