Visualization has proven its value in scientific advances by helping scientists gain insight from their data and verify scientific computations. The amount of scientific data collected from sensors and simulations can easily be on the order of petabytes of data. Visualization of this large-cale data requires cluster computing, and more often than not distributed computing over high-speed networks, as the size of the data exceeds the capacity of the average computing clusters, and the data may not even reside locally. To view visualizations of large-scale data at or near native resolution, scalable tiled display walls are increasingly being used for scientific visualization.

In this context, the Scalable Adaptive Graphics Environment (SAGE) has been developed to support large-scale data visualization in a distributed visualization environment that includes ultra-high resolution scalable tiled displays. It is a specialized middleware that enables real-time streaming of extremely high-resolution graphics and high-definition video from remotely distributed rendering and storage clusters to scalable display walls over ultra high-speed networks. This dissertation extends SAGE to support distant collaboration between multiple endpoints.

In the SAGE framework, each visualization application streams its rendered pixels to the virtual high-resolution frame buffer of SAGE, allowing users to freely move, resize and overlap the application windows on the display. Every window movement or resize operation requires dynamic and non-trivial reconfigurations of the involved graphies streams. These reconfigurations become even more complex when SAGE is required to support multiple collaboration endpoints with different tiled display configurations and application window layouts.

Visualcasting is a new SAGE network service to address this problem using a high-speed bridging system that receives pixel streams from rendering clusters and that duplicates and sends them to each end-point. This enables distant collaboration among international researchers in scalable display environments. Using the Visualcasting service, collaborators can share their visualizations and interact with each other through high-definition video conferencing in the SAGE Framework.