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....... are crucial. 6.5 mbps data rate is necessary in a multi-addressable
environment. SCSI I gives only 7 addressable ID locations, SCSI II supports
127. Fast SCSI II gives 5 mbps, Wide SCSI II gives 10 mpbs, although lags
in SCSI port-to-CPU data bus bring this number down. Fast and Wide SCSI
II supports 20 mbps, but Ultra SCSI III gives us 40 mbps. SCSI III boards
require PCI hardware for achieving maximum data throughput and get realworld
speeds above 5.4 mbps. There are firmware issues involved. There must be
compatibility between the acceleration hardware, its firmware and the driver
software, especially in a RAID environment. RAID is the optimum solution
to such data intensive situations. RAID level 0, RAID level 1, RAID level
2, RAID level 6, RAID level 10. Striping, RAID level 0 makes each linked
drive write in sequence with no error checking routines or data redundancy.
Mirroring, RAID level 2, writes the data in tandem across 2 drives, where
one drive always assumes the role of the source mirror. Do you have independent
power supplys for all devices in the SCSI chain? How much redundancy is
built into your storage system? Are all elements fully hot swapable? Will
your Ultra SCSI III device be translatable into FireWire with the arrival
of the Common Hardware Reference Platform Machines later this year? Will
your storage devices benefit from upgrading your LAN to 100 base-T? Does
your existing network fully implement Phase 2 ethernet? Are there hidden
pockets using Phase I protocol that will prevent you from moving beyond
10 base-T?