Library » 1996

Ultra2 SCSI - The Evolution Continues

Ultra2 SCSI - The Evolution Continues (PDF)
A White Paper Prepared by Dean Wallace of Linfinity, for the SCSI Trade Association

This white paper defines and describes the Ultra2 SCSI physical interface and discusses differential signaling. The advantages of the parallel SCSI interface and the evolution of parallel SCSI, including SCSI-1, Fast SCSI, Fast Wide SCSI, Ultra SCSI and Wide Ultra SCSI, are discussed.

SSA and Fibre Channel Myths and Realities

SSA and Fibre Channel Myths and Realities (PDF)
A White Paper prepared by Greg Schulz of MTI, for the SCSI Trade Association

This paper reviews some myths about IBM® Serial Storage Architecture (SSA), Fibre Channel (FC) and traditional Small Computer System Interface (SCSI) technologies. Some will argue that parallel SCSI is at or near the end of its life cycle while SSA is a newly established architecture with Fibre Channel still evolving. SSA and Fibre Channel, including Fibre Channel-Arbitrated Loop (FC-AL), share many common characteristics:
  • Both are serial architectures sending a stream of bits over a communication path
  • Both use fiber optics to digitally transmit high-speed serial bit streams
  • Both support more devices over longer distances than parallel SCSI
  • Both are open standards although SSA is perceived as an IBM proprietary protocol
  • Both provide improved bandwidth compared to traditional parallel SCSI with FC being
  • faster
The following are some myths and realities involving SSA, Fibre Channel and parallel SCSI. Similar to parallel SCSI, which evolved from SCSI-1 to SCSI-2 and now SCSI-3, Fibre Channel is deliverable today while still evolving. SSA has also evolved into a stable product with limited support from the industry.

Advances In SCSI Parallel Interface Technology (PDF)
A White Paper prepared by the SCSI Trade Association

The Interface Dilemma:
The computer's insatiable appetite for higher I/O performance is now further accentuated by the Internet, network servers, multi-media, video-on-demand and other demanding applications. More users need more data from more devices at higher speeds, while expecting greater levels of reliability, availability and serviceability at lower costs.