NPACI

 

Legion

University of Virginia (A. Grimshaw)
Stage 3

Computer networks are becoming larger, faster, and more powerful and offer new opportunities. Gigabit networks, connecting powerful high-performance machines and workstations, offer enormously powerful infrastructures that can solve complex problems and distribute huge amounts of information. To take advantage of this, the connected resources can be linked together to make a single, worldwide, virtual computer. This virtual computer requires easy-to-use software that can manage a complex physical system and support large degrees of parallelism for the user.

Legion, an object-based metasystems software project at the University of Virginia, is designed to build a system of millions of hosts and trillions of objects, tied together with high-speed links. Users working on their home machines have the illusion of working on a single computer, with access to all kinds of data and physical resources, such as digital libraries, physical simulations, cameras, linear accelerators, and video streams. Groups of users can construct shared virtual work spaces, to collaborate research and exchange information. Legion supports this abstraction with transparent scheduling, data management, fault tolerance, site autonomy, and a wide range of security options.

Over time, of course, there will be new requirements and new opportunities for distributed computing, and future users will make unforeseen demands on resources and software. Legion is therefore an open system, designed to encourage third party development of new or updated applications, run-time library implementations, and core components.

Legion sits on top of the user's operating system, negotiating between the computer's resources and whichever resources or applications are required. Legion handles resources scheduling and security issues so that the user isn't bogged down with time-consuming negotiations with outside systems and system administrators. Legion offers a user-controlled naming system called context space, so that users can easily track and use objects in farflung systems. Users can also run applications written in multiple languages, since Legion supports interoperability between objects written in multiple languages.

For more information, see http://legion.virginia.edu. To see Legion in action, see http://legion.virginia.edu/StatusMonitor/Status.html.

[NPACI Roadmap]
[AppLeS] [ATLAS] [HyperSQL] [KeLP] [LAPACK]
[Legion] [Metadata browser] [NetSolve] [Planguages]
[QueryDesigner] [QML] [ScaLAPACK]

Last modified: Mon Jan 25 15:48:37 1999