The integration of real-time I/O and network support in the Stony Brook Video Server

Stony Brook Video Server is an Ethernet-based video server from the Experim ental Computer Systems Laboratory, SUNY at Stony Brook, and has been fully operational for over a year. SBVS employs only off-the-shelf PC components and Is capable of guaranteeing real-time delivery of digital video streams from the servers disk subsystem, through a shared LAN, to an end user's dis play. SBVS integrates a real-time software-based disk array with Real-Time Ethernet Protocol to provide end-to-end bandwidth guarantee. This article d escribes in detail how the real-time I/O subsystem interacts with the RETHE R subsystem, and the performance cost of this integration. The most recent version of SBVS, a Pentium-90 PC with a six-drive disk array, con support v p to 45 simultaneous MPEG-1 (1.5 Mb/s) streams with a single 100 Mb/s Ether net link, and up to 65 streams with two 100 Mb/s Ethernet links.