ATTO Technology V-Class Network Card User Manual


 
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ATTO Technology Inc.
Appendix A ATA Disk Technology
ATA is the dominant disk drive technology. 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. Exhibit A-1 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.
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+