ATTO Technology Diamond Storage Array VT-Class - Manual (Page 84)

A-iii
ATTO Technology Inc. Diamond Storage Array Installation and Operation Manual
Appendix B ATA Disk Technology
ATA is the dominant disk drive technology today and will be for the foreseeable future. It offers all the cost
advantages of a mass produced, consumer-driven technology which is rapidly being driven forward. Today ATA
also offers all the performance and reliability features needed to create high performance ATA-based disk storage
arrays.
We view ATA as the perfect disk drive technology for
“in-the-box” disk storage array solutions.
Aggregated Data Interface Technology (ADXT
™)
with its built-in Virtual Device Manager (VDM), Data
Routing Fabric (DRF) and ATA Interface Engines
(AIE) smoothly and efficiently organizes Fibre
Channel data streams for storage or retrieval on ATA
disk drives. ADXT provides end users with the power
and sophisticated data control needed to take
moderately priced ATA disk drives combine them in a
disk storage array and power them to the performance
levels of SCSI or Fibre Channel disk arrays
Unlike other storage arrays which use expensive SCSI
or Fibre Channel disk drives to achieve performance,
the Diamond Series uses lower cost ATA disk drives
combined with an intelligent midplane to create a
storage array with exceptional price and performance
characteristics.
ATA disk drives are used in the enormous PC
marketplace and an estimated 85% of all disk drives
sold today contain an ATA interface. Shipments of
ATA drives are expected to grow rapidly over the next
five years with increasing consumer and business
demand. In general, ATA disk drives are the “driver”
of all disk storage technology as the costs, volumes
and demands of the PC marketplace are the primary
focus of the world’s largest disk drive manufacturers.
ATA disk drives today offer capacities comparable to
SCSI and FC disk drives – although at a tremendously
lower cost. Advances in platter and head technology
will push drive capacity along a very steep curve in the
next five years. The chart below summarizes ATA and
other disk interface standards. It clearly indicates that
ATA drive technology offers characteristics that
ideally suit it for “in the box” usage in high capacity,
high performance disk arrays.
Disk features and standards
Feature IDE ATA SCSI Fibre Channel
Connectivity
• Max Devices
• Cable Length
2
46 cm 2
46 cm 16
25 m 126...millions
10 km
Performance
• Bandwidth
• Bandwidth/drive
• Multi-threaded I/O
16 MB/sec.
8 MB/sec.
No 100 MB/sec.
33 MB/sec.
Yes 160 MB/sec.
10 MB/sec.
Yes 200 MB/sec.
1.6 MB/sec.
Yes
Max Initiators 1 1 <16 125...millions
Topology Bussed Bussed Bussed Loop/Fabric
Error Detection None Yes Yes Yes
Protocol “weight” very light light medium to heavy heavy
• Cost
• Interface
• Drives
n/a
n/a lowest
lowest medium to high
medium to high highest
medium to high
Manageability none low to medium medium medium+