PITTSBURGH -- Upgrades to hardware and fiber-optic cable at Pittsburgh's high-performance network hub have dramatically improved connections to LeMieux, Pittsburgh's terascale system. These upgrades, which provide a more than tenfold boost to bandwidth between LeMieux and Abilene -- a high-performance network backbone -- will facilitat computational research by scientists and engineers nationwide. The recent upgrades quadrupled bandwidth between Abilene and the Pittsburgh GigaPoP -- a high-speed network crossroads that serves higher education and research. The upgrades also improved the link from the GigaPoP -- short for Gigabit Point of Presence -- to LeMieux by more then tenfold. "These upgrades," said Gwendolyn Huntoon, who directs PSC's National Center for Network Engineering, which administers the GigaPoP, "allow LeMieux to support applications with much higher distributed data requirements including higher aggregated data rates -- multiple users with large data transfers -- and large single-stream transfers." One such application is "tele-immersion" -- a term for using computer vision technologies to foster realistic human interaction across geographical distance. Tele-immersion involves an array cameras at each location providing multiple angles of view that are reconstructed into a realistic 3D image at the other end, creating the illusion that people, who may be thousands of miles distant, are in the same physical space. The challenge is to transfer data from the cameras, process the video streams into a 3D view and deliver the result in real-time, impossible without a lightning-fast network, such as Abilene, and the enormous processing power of LeMieux. Through an award from the National Science Foundation Information Technology Research program, PSC networking experts and programmers are helping researchers at the University of North Carolina, Chapel Hill and the University of Pennsylvania to develop a prototype tele-immersion system. At the SC2002 conference in Baltimore in November, a tele-immersion demonstration connected two side-by-side booths on the convention floor. Data from one booth traveled first to Pittsburgh for processing by LeMieux then back again to the other booth. Due to the network upgrades, the demonstration achieved sustained data rates of up to 700 Mb/s -- faster than the GigaPoP's previous Abilene connection and at least four times faster than the connection to LeMieux. "This was an application," said Huntoon, "that we obviously couldn't have supported before the upgrades." Bandwidth from the GigaPoP to Abilene improved from 622 million bits per second (Mb/s) to 2.4 billion bits per second (Gb/s) and the link to LeMieux is improved by a factor of 13, from 155 Mb/s to 2 Gb/s.