BOOK_CONTENT
From Video and Media Servers: Technology and Applications, Second Edition

Overview

Not long after SCSI-1 was first introduced, its drawbacks became evident. Soon the need for a more advanced interface became obvious and the industry began what would be a long cycle of drive interface advances. The second step in our SCSI overview takes a brief retrospect of SCSI-1 versus SCSI-2 differences, then moves directly into the development and technology of SCSI-3 the next generation in connectivity and addressability.

Bandwidth, data transfer performance, and the number of large blocks of data being transported are all considerations for improving SCSI performance. While desktop, multimedia and video applications continue to grow, the need for implementation of enhanced bus performance becomes crucial. As SCSI transfer rate performance has increased, more applications are brought to market and the success of media servers for multimedia, non-linear editing, and video applications has soared.

Industry tests conducted in 1995 were already showing substantial improvements by using the newer and faster SCSI system protocols, especially as the block or file size transfer rates increased. The expectation of a future SCSI-3, under construction as early as 1993, changed the general perception that SCSI, as a command set protocol, may continue for quite some time.

The Next Step in SCSI

The final acceptance of SCSI-2 came in 1994, when ANSI approved the X3.131-1994 standard. We recall that a major improvement from SCSI-1 to SCSI-2 was the inclusion of the Common Command Set (CCS). The final standard included some otherwise optional sections of SCSI-1, but now made them mandatory in SCSI-2.

Backward...

Copyright Butterworth-Heinemann 2001 under license agreement with Books24x7

Products & Services
SCSI Adapters and SCSI Controllers
SCSI adapters and SCSI controllers (SCSI cards) are computer interface cards that are installed in an expansion slot. They are used to connect the SCSI system to several devices and peripherals using a daisy chain method.
SCSI Cables
SCSI cables are used for high-speed bus connections between small computers and intelligent peripherals such as hard disks, printers, and optical disks.
Bus Extenders
Bus extenders are used to increase cable lengths for distance-limited bus protocols.
Network Cables
Network cables are used in the transmission of data across networks. Choices include Fibre Channel, FireWire or IEEE 1394, GPIB, serial, parallel, patch, SCSI, Ethernet and USB.
SCSI Terminations
SCSI terminations are electrical circuits placed at each end of a SCSI cable for impedance matching. They are an important part of any small computer system interface (SCSI) that uses hard drives, CD-ROMs, scanners, tape drives, or other SCSI peripherals controlled by a SCSI bus.

Topics of Interest

Overview Fibre Channel, at the conclusion of 1997, was viewed by many as the most probable method of intra-facility interconnection for the high-speed transfer of video and data around the broadcast...

Small computer systems interface (SCSI) is an intelligent I/O parallel peripheral bus with a standard, device-independent protocol that allows many peripheral devices to be connected to the SCSI port.

SCSI-2 has significant improvements over SCSI-1 including faster data transfer rates, better connectors, wider bus path, better reliability via synchronous negotiation, and parity checking. SCSI-2 has...

Overview The past several years have placed an increasing burden on I/O subsystems, the direct result of an insatiable appetite for increased storage requirements for more data. This creates a...

Compression Technology Video compression technology has enabled more data to be stored in much less space. The 25 Mb/s motion-JPEG (M-JPEG) systems of several years ago have now migrated to MPEG-2...