Developments in the mid-range and enterprise backup markets have always been far more interesting than those at the entry-level, as vendors frantically strive to out-do each other in terms of storage capacity and performance. We’ve already seen the second generations of SDLT and LTO Ultrium. In September this year IBM proudly announced that its latest TotalStorage Enterprise Tape Drive 3592 was the world’s highest capacity enterprise tape storage device. Well not any more it isn’t, as barely two months have passed and Sony now steals IBM’s thunder with the introduction of its all-new S-AIT format. The 300GB offered by the 3592 initially looks impressive but the StorStation SAITe1300 raises the bar with a staggering native capacity of no less than 500GB. The drive can’t match IBM’s claimed native 40MB/sec transfer rates but it comes a close second with Sony quoting 30MB/sec. Another key factor is that Sony’s product roadmap indicates that the second generation isn’t far behind and will be the first tape format to break the magical 1TB barrier for native storage on a single cartridge. S-AIT isn’t a completely new format as Sony has taken its well established AIT format and modified it to work with 1/2in. cartridges. Helical scanning, as used on all AIT, DDS, VXA and Mammoth drives, is still the preferred recording technology. But Sony has taken advantage of the much higher recording densities, allowing it to offer far higher capacities than linear recording methods. Sony was also well aware that to compete in the enterprise backup market it needed to deliver a form factor that didn’t require autoloader and library manufacturers to modify existing systems to suit. So, the internal S-AIT drive has been engineered to fit in the same physical space as competing formats. The external drive on review is very solidly built with a smart electric blue plastic cover protecting the drive innards. A small button manually releases the flap, although for the price we would have expected nothing less than a motorised cover and locking capabilities. For performance testing we called in a PIII 866 server equipped with 1GB of memory and running Windows 2000 Server/SP4. A single Seagate Cheetah Ultra320 hard disk linked to an Adaptec Ultra320 adapter card dealt with general storage. The tape drive was connected to its own Adaptec Ultra160 SCSI host adapter to ensure there were no resource contentions. Mishmash of data
We found installation under Windows 2000 Server simple enough as it uses the same driver as Sony’s AIT devices. Backup software came courtesy of Veritas Backup Exec 9 and Computer Associates ARCserve 9. We used a 18.5GB mishmash of data to represent a typical workgroup server, which consisted of a variety of Word documents, Excel spreadsheets, Access databases and PowerPoint presentations, along with HTML files, program installations, video clips, bitmaps, sound files and Acrobat .PDF files. For both software platforms the drive was asked to backup and verify the test data and then restore it to its original location. Finally, to confirm the test system itself was not going to create a bottleneck we ran the open source Iometer utility to test disk performance which reported average read rates for the Seagate drive of 64MB/sec and write rates of 61MB/sec. The SAITe1300 demonstrated that it was capable of delivering the quoted native transfer rates with Backup Exec and ARCserve reporting average backup speeds of 1,809MB/min and 1,798MB/min respectively. Verification speeds for ARCserve’s tape to disk comparison and Backup Exec’s tape read test were marginally lower but user’s won’t have to wait long for data to be returned to active duty with ARCserve delivering the highest restoration rate of 1,021MB/min – noticeably faster than the current SDLT320 and Ultrium 2 drives. As a mid-range backup solution the StorStation SAITe1300 is a costly option, particularly as Hewlett Packard’s StorageWorks Ultrium 460e costs under £4,300 - around a third the price. S-AIT is also not backward compatible with earlier formats, either, although this drawback doesn’t appear to have severely affected the take-up of Ultrium which suffered the same problem. Move up to the enterprise however and the Sony alternative starts to make sense as it costs substantially less than IBM’s and StorageTek’s offerings and also beats them soundly for storage capacity.


Price, performance and capacity are three key factors when choosing the best format for backup and, at the enterprise level, Sony scores highly in all these categories. This market is where Sony is pitching this product and as such the mid-range market will find the SDLT and Ultrium formats far more cost-effective backup solutions.