This Techworld document tabulates details of the StorageTek 9840 and 9940 formats. The 9840 is a fast access format with lower capacity than the 9940 which is a high capacity format. StorageTek designs its drives for long duty cycles in enterprise environments with high tape usage rates. The company asserts that LTO, SDLT and S-AIT formats, the open systems formats, are not designed for such continuous usage. Martin Warren is StorageTek's business manager for advanced tape solutions and says, "The 9940 is for use over sustained periods of twelve hours a day. People will pay a premium for this."

This has two generations, A and B, and no further iteration has been discussed by StorageTek.

9840(A) 9840 (B)
Raw Capacity 20GB 20GB
Compressed Capacity 40-80GB 40-80GB
Raw Transfer Rate 10MBps 19MBps
Compressed Transfer Rate n/a n/a

The 9840 is a linear format and has ESCON, UltraSCSI and Fibre Channel connectivity options. The compression method is enhanced LZ. StorageTek tends not to quote compressed data capacity or throughput figures. Warren says, "Some data won't compress. Other data compresses a lot. I've known a customer get a 5:1 compression ratio with mainframe data. The most I've come across is 6:1."

StorageTek's view of what customers want in the next generation is performance, capacity and high reliability, not sheer access speed on its own. That indicates the 9940 is the focus going forward.

LIke the 9840 this is a half inch linear tape format but it is capacity-centric in design. Again, like the 9840, there are A and B generations but a third (C?) generation is in its early beta test phase and fourth and fifth generations are being mooted.

StorageTek has announced alliances with Imation and Fujifilm to develop tape media for the third generation. Techworld has previously stated, 'IBM's recently announced 3592 holds 300GB and it uses Fujifilm's Nanocubic coating technology. LTO3 will hold 400GB next year and Sony's SAIT holds 500GB.' This sets the general bar for StorageTek's next generation 9940.

T9940A T9940B T9940C? T9940D? T9940E?
Raw Capacity 60GB 200GB 500GB? 1TB? 2TB?
Compressed Capacity 120-240GB 400-500GB 1-1.25TB? 2-2.5TB? 4-5TB?
Raw Transfer Rate 10MBps 30MBps 50-60MBps? 100-120MBps? 200-240MBps?
Compressed Transfer Rate to 37MBps 60-75MBps 100-120MBps? 200-240MBps? 400-680MBps?

The T9940A and T9940B are current. The third generation, possibly to be called the T9940C, will likely start shipping in the fourth quarter of 2004 with full availability starting in 2005. The fourth and fifth generations may appear in 2006 and 2008 respectively. Warren says that investment protection through the ability to use earlier generation tapes in later generation drives is crucial to StorageTek's customers.

The T9940C's raw capacity should be at least 500GB and may be larger. The general pattern with future generations is to double capacity and transfer rate every two years. Warren concurs with this and observes that it should be what StorageTek will do at a minimum.

So a terabyte 9940-class tape for 2006 is possible. StorageTek is hoping that these capacity and throughput numbers, combined with its heavy duty usage capabilities, should enable the company to hold on to its existing customers and even win new ones.