Last week we started to discuss Web operating systems (otherwise called Webtops). To briefly recap, these systems emulate a Windows multiapplication operating-system environment using AJAX or flash applications executing in a Web browser, sometimes with additional back-end processing handled by a remote server.
Web operating systems provide an infrastructure for managing Web applications, their active data and configurations, and their interaction with each other.
Webtops can run on any modern browser on any operating system, and because the user configuration is stored on a remote server, the Web operating system should run from anywhere.
We must mention that Web operating systems have nothing to do with WebOS, a research project started in 1996 at University of California, Berkeley. That project is described as: "WebOS provides basic operating systems services needed to build applications that are geographically distributed, highly available, incrementally scalable and dynamically reconfiguring."
WebOS paved the way for projects such as Legion, "an object-based metasystems software project at the University of Virginia . . . designed for a system of millions of hosts and trillions of objects tied together with high-speed links."
The Legion project was the foundation of the Centurion test bed, which, according to its home page, can deliver more than 240GFlops using 384 processors (that's 0.625GFlops per processor).
Centurion has produced remarkable performance, such as 3.7GFlops using 49 nodes, or 0.0755GFlops per processor. With an equipment cost of just $20,000, that equates to just $5,405 per GFlop.
Now we need to stop digressing.
An example of a current and useable Web operating system is the subject of the 800th issue of the "Network World on Web Applications" newsletter. The issue contains a review of an interesting open source Web operating system project called eyeOS, which has a back-end written in PHP that creates a client-side Webtop and applications using AJAX.
You can, if you like, build your own Webtop. The foundation of a Webtop system requires a manager to create and manage windows in a browser display. Over the past few months a number of excellent products have appeared, and one that impressed us was Winlike from Ceiton technologies.
Winlike is a purely dynamic HTML-based system and remarkably only 27KB in size. It works with Microsoft Internet Explorer 5.5 or higher, Netscape Navigator 6.1 or higher and the Mozilla family of browsers (Mozilla 0.92, Firebird 0.7, Galeon, Avant) without plug-ins.
At the heart of Winlike is the Window-Manager, which manages the set of overlapping windows you want to use. The Window-Manager provides functions for creating, closing, moving and minimizing windows, and handles all the rendering issues of supporting overlapping windows.
Winlike includes an editor for configuring Winlike windows that generates the code to include in your Web pages.It includes an API so you can create anything from a simple multiple-window display to a complex, dynamic environment for dashboards.
We tried building a Winlike system with flash content generated by Crystal Excelsius, and it was ridiculously easy! Oh, the Web Applications newsletter also covered Xcelsius.
Winlike is free for noncommercial use and for development purposes. For a commercial Web site or Web application, a single server license is $80. Volume server licenses are also available.