The ability to exploit and enhance the existing powerful graphics capabilities on COSMOS to enable Grid based collaborative visualizations with the local Cambridge network, and more widely to within the COSMOS and Planck consortium is key to the project.
The COSMOS consortium was one of the first sites to install and provide feedback on a beta version of SGI's Visualization Serving software (Vizserver), a visualization application which allows remote network access to the Onyx2 graphics rendering hardware through fast OpenGL compression/decompression algorithms. Very good performance has been demonstrated over the 100Mbit/s local network, thus allowing the real-time manipulation of large data sets on the COSMOS supercomputer at workstations remote from the graphics head. For example, cosmological Vizserver applications were demonstrated remotely to the Chancellor of the University at the opening of the Centre for Mathematical Sciences last year.
The recent launch of SuperJANET IV with a gigabit backbone should allow remote COSMOS consortium users beyond the local network also to benefit. An initial step in demonstrating the utility of Vizserver will be to integrate the COSMOS Onyx with the (PC-based) Cambridge E-science Access node. This will allow immediate communication with other regional centres, as well as internationally.
Virtual Director from the NCSA is a powerful suite of collaborative visualization tools su ciently exible to be tailored to the needs of the COSMOS consortium. Virtual Director allows for the real-time update of visualization parameters for the viewing of mirrored data sets at remote sites. It supports visualization applications suitable for a wide variety contexts, ranging from isosurfaces on cartesian grids, point-particle distribution mapping, through to unstructured grid rendering needed for adaptive mesh refinement.
We have already initiated a collaboration with SGI and the NCSA to implement Virtual Director on COSMOS and to develop tools which will allow consortium members to seamlessly interact and collaborate on large cosmological data sets. A collaborative visualization session between Cambridge and the NCSA will demonstrate Virtual Director this November at Supercomputing 2001. Further work to be carried out includes enhancements to the Globus toolkit, creating interfaces, metadata tags and the replica management of data at remote sites, which will be necessary for effective use of Virtual Director for consortium collaborations.
In addition, we anticipate using this grid-based toolkit to incorporate remote pipeline 5 control using visualization steering. This role will include support for the development of two- and three-dimensional interactive packages already created to visualise CMB data on a sphere or in projection (e.g. CSKY). These will be developed so that they can be used remotely and interactively under Virtual Director. This will have obvious interdisciplinary applications for other similar data sets and we will make these tools available through the Virtual Science Network and elsewhere.