The benefits of server-based computing and thin clients in many environments are not in doubt. Hardware and electricity costs can be reduced, and thin clients are more reliable than PCs, but for most people the key benefit will be the ability to centralise application and desktop management.

The problem for many companies is the cost of the extra software needed. Even though Microsoft now embeds Windows Terminal Services (WTS) within the operating system, it is not free to use as it also requires client access licences (CALs). Plus if you want the extra management capabilities offered by Citrix MetaFrame, you can expect to pay even more.

"Citrix is an expensive add-on," says Guy Watts, sales director at technology reseller and thin client user Gtech. "Why pay £250 per seat for Citrix when you can get 80 percent of what you need with Windows Terminal Services?"

He says the problem is that WTS gives you a lot of what you need, but not the management and reporting that you get with Citrix, plus Microsoft's RDP client protocol is not as network-efficient as Citrix's ICA protocol. In addition, WTS cannot publish an application, only a complete desktop.

Gtech's answer, both for its own use and for its customers, was to look elsewhere for those server-based computing (SBC) management capabilities. It chose CockpIT from Israeli software company Jetro, an add-on tool that only requires one server in addition to the WTS server farm.

"It's about £70 per user - we are mainly a hardware distributor and this is a solution where cost may be an issue," Watts says. "It's going down very well with people who've started to embrace thin client but are hesitating because after spending £20,000 with Microsoft for 100 users, they now need to spend the same again with Citrix for management.

"Jetro can sit on top of a mixed RDP and ICA environment, for example we have a couple of hundred thin-client users, a couple of dozen of whom are remote users running ICA with the rest using RDP. So we installed Jetro, and our admin people can use CockpIT to manage both.

"Microsoft has improved WTS over the years but it still doesn't have the features of Citrix or Jetro, and while Windows Server 2003 narrows the gap between WTS and Citrix, Jetro closes it still further. Plus, like Citrix, Jetro can provide reporting, load balancing, seamless windows and remote printing, but it can do them on just an RDP client."

Publishing non-Windows apps
Something else that WTS cannot do on its own is publish non-Windows applications, adds Martin Niemer, a product manager for German thin-client manufacturer ThinTune. "In Germany we see more and more acceptance of Linux and Open Office on the desktop - the way for Linux into the desktop market is to adopt MS Office features," he says.

Of course, you could use X-Windows to do server-based computing, but it has a high protocol bandwidth. Niemer suggests the answer could be a WTS alternative such as Tarantella, a spin-off from SCO (before it went all litigious) which does also terminal services for UNIX and Linux, or a tool called NoMachine which he says adapts the X-Windows protocol to run even faster than Citrix ICA.

Other SBC tools include DAT Panther Server, which adds application publishing to WTS, and GraphOn's GO-Global, which has the advantage of supporting a wide range of both servers and clients. It can publish Linux applications as well as Windows and UNIX, and it has clients for all three plus for Java. That means a user can run a server-based Windows or Linux application remotely in any Java-capable Web browser.

(Some of this software is discussed, along other client software, in a useful SBC backgrounder to be found here.)

More can be done in a thin client too, such as attaching a local scanner or DVD drive, or running a character-based terminal and a Web browser.

Thin client vs Windows PC
"Big customers always have legacy apps running in ASCII mode, plus maybe a Citrix farm for MS Word and so on," Martin Niemer says. "You can emulate a terminal on the server or on the thin client - most users prefer the latter. Many employees only need the ERP system and email, say, so buying Microsoft licences is a waste of money when they could use Webmail.

"Citrix has nearly 100 percent of the enterprise market but it's very expensive - around 300 Euro per seat - and others such as Jetro or Tarantella can give 80 percent of the features for a third of the price. Resellers want an alternative to Citrix too, because everyone sells Citrix."

Other local needs which require extra software include printing and file transfer between local and remote applications, says Itamar Banayan, Jetro's sales and marketing VP. "SBC came with a promise of solving many problems, but in doing that it created new problems, for example, printing at the client site over a narrowband link," he says.

"The entire SBC industry is based on Windows Terminal Server (WTS), it is the core technology," he continues. "Then you can install our software or Citrix's on top. You can add our software over Citrix for printing - we have special pricing which enables mixed deployments of CockpIT, MetaFrame and WTS. SBC is good but it's not for everyone. Not all applications run on WTS either."

Martin Niemer adds that the need for extra software also depends very much on the size of the organisation. "With Windows 2003 and RDP version 5.2, most of the features people needed Citrix for are already there," he says.

"So we see companies with 100-150 desktops that are not considering Citrix, just Windows 2003, because they don't need the enterprise management capabilities. Above that there is still a Citrix market, but it's hard for others such as Jetro, in the 200-300 user market."

Citrix goes large
Keith Turnbull, Citrix's VP of mobility product development, says that the company's move towards larger users was a deliberate response to the growing capabilities of WTS.

"Our target is 500 users and up - medium to large enterprises," he says. "To be honest, a 25-user shop can run standard Terminal Services quite adequately, whereas a large environment has security and management issues; for example, password management is much more of a problem."

He adds that while rivals might try to fill the 100 to 500 user gap more cheaply, the only reason they can be that much less expensive is that they cannot match the functionality offered by Citrix, which is after all the company that originally invented server-based computing.

Nor is he worried about Microsoft enhancing WTS to steal Citrix's market, he says - not least because every sale for Citrix MetaFrame is de facto also a sale for Microsoft Windows.

"We have a huge value-add on top of WTS," he says. "MetaFrame is just one part of the suite - there are many more access problems that people need solutions for. For example, IDC breaks the access infrastructure market into 14 categories, and we map to nine of those.

"Typically you get competitors who build a cheaper version 1.0 - it's where you were three to four years ago. You can't really compare it, there's a whole raft of things those products don't have, such as smooth roaming, delegated admin, and so on."