Citrix Presentation Server (formerly known as MetaFrame) and Windows Terminal Server are two examples of 'thin client' technologies which replace a standard networked PC with a cheaper client. The 'client' simply provides access to applications running on a server.
What are the problems?
There are a couple of issues facing access technology users wishing to operate in the thin client environment:
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The client machine may not be a PC at all. This means that access technology, such as screen magnification software and speech output systems, cannot even be installed.
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Access technology installed on the client machine cannot interpret any text displayed in the thin client window. A screen reader installed on a client PC sees a large graphical image. A magnification system should be able to magnify this image, but cannot track the focus of interest for the user, making any application running in the window largely unusable.
What are the solutions?
Access technology that is intended to operate within the thin client environment has to be a special version designed to be installed on a Terminal Server.
Some access technology manufacturers are now selling products that are designed to run on a Terminal Server in this way.
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GWMicro was the first to develop a Terminal Server version of its screen reader Window-Eyes.
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Dolphin Computer Access has produced a version of its combined magnification and screen reading product Supernova Access Suite.
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There are also versions of JAWS screen reader and MAGic screen magnifier from Freedom Scientific that incorporate Terminal Server capability.
It is also possible to keep a PC outside the Terminal Server regime, perhaps maintaining a networking solution that existed before the thin client network was introduced. This would mean a PC linking into the server in a different way. This allows the video and data processing to be done locally, enabling the screen contents to be 'visible' to a screen reader or magnification system.
This solution is not without its difficulties. However, we are aware of employers who have fulfilled their obligations under the Disability Discrimination Act by providing their disabled employees with equivalent access through a networked PC.