Partitioned AIT

Advanced Intelligent Tape (AIT) for Tandem gives the mainframe-class capacities and throughput, high-speed restore with complete 5190 emulation for seamless integration.

Access To Data
Tape technologies continue to provide higher capacities and transfer rates every 18 to 24 months, but better access to data has become very limited. Tandem users, needing critical data at rapid speed, often forgo new technology and high capacity solutions to maintain fast access of files on small capacity cartridges such as 18- and 36-track technology. Time and labor is usually intensive because of the huge inventory and difficult management of small capacity cartridges.

Need for Capacity
Tandem users often look to DLT drives for higher capacity and less tape handling. Usually the full capacity is never reached because of slow transfer rates or small jobs, using only a fraction of the expensive tape. Speed to data becomes critically slow for most high capacity cartridge users due to the sequential search through huge amounts of data stored on each tape.

The Solution
Partitioned AIT delivers rapid access to stored data plus tremendous capacity, merging the best of 36-track technology with the high capacity of AIT technology by the use of partitioning. Using a captive, non-volatile memory chip, known as Memory-In-Cartridge, or MIC, the drive segments each data cartridge into partitions, which the Tandem identifies as individual tapes. The number of partitions is user-definable from the front panel of the drive. Because AIT can position the cartridge very rapidly (average: 60 seconds) to the correct segment of tape, a file can be located in a specific partition, eliminating search time of any other segment of tape. On a full DLT cartridge, the same file restore operation can take 10 to 50 times longer.

Think of a single data cartridge as a "virtual stack" of tapes in a 5194ACL, able to write single small jobs to each partition, equivalent to an individual tape, or large jobs over several partitions. It can even be configured in a loop to continually write new data over its own scratch partitions. The low cost per gigabyte for a high capacity tape is now achievable because the entire 25 to 50 gigabyte data cartridge (65 to 130 GB at 2.6:1 compression) can be used from beginning to end.

Easy Migration
From K- to S-Series our series of AIT drive solutions emulate a standard 5190/5194/5196 as a plug-and-play replacement. With any of our partitioned AIT configurations, the drive appears to the host as a 5194/5196 Automatic Cartridge Loader (ACL) tape subsystem. This means that our drives work on Tandem's standard tape interfaces such as K-based 3216, as well as S-based PMF, IOMF and ServerNet D/A. As you move to S-Series, the AIT drive not only moves with you, but is a high-capacity migration tool too.

Technical Specifications

  • Plug-and-play with Tandem NSK® platforms
  • 5190/5194/5196 emulation
  • User-definable partition configurations
  • Easy-to-understand LCD with mode select
  • No routine cleaning required
  • Universal power supply
  • Drive Models
    SS 135-50 & SS 135-100 single-drive AIT-1 & -2 subsystem with 25/50 GB native capacity
    user-definable partitioning
    and FlashRestore™
    Autoloaders TL 4210/4220 aIT tape autoloaders with one or two drives
    12 or 22 cartridges
    up to 2.86 TB (AIT-2) or 2.0 TB (AIT-1) capacity
    user-definable partitioning
    and FlashRestore™
    High Capacity Tape Libraries various configurations available from 2-12 drives
    12-360 tape cartridges with capacities ranging up to 50 TB
    with partitioned tapes, up to 23.040 logical tapes online.
    Feature AIT-1 AIT-2 5194 (3490E) DLT4000/7000
    Capacity (native) 35 GB 50 GB 800 MB 20/35 GB
    Typical Compression Ratio 2.6:1 using ALDC 2.6:1 using ALDC 1.82:1 using IDRC 1.81:1 using DLZ
    Sustained Transfer Rate (native) 3.0 MB/s 6.0 MB/s 3.0 MB/s &nsp;
    Media Load Time < 10 sec < 10 sec 13 sec typical 48 sec
    Average File Access Time < 27 sec < 27 sec 55 sec 68 sec
    Drive MTBF (duty cycle %) 300,000 Hrs (60%) 300,000 Hrs (60%) 150,000 Hrs (50%) 200,000 Hrs (50%)
    Average Head Life > 50,000 Hrs > 50,000 Hrs 6,000 Hrs 10,000 Hrs
    Power Consumption 12 Watts 12 Watts 150 Watts 25 Watts
    Drive Warranty 3 years 3 years 1 year 3 years

    *Information based on published specifications by Sony, Tandem, Fujitsu, and Quantum as of 2/10/99. All data is based on drive specifications, actual performance on Tandem systems vary with size, block size, application, controller, system load, and system type.
    AIT-1 and AIT-2 Drive Specifications
    InterfaceAIT-1 SCSI-2 Fast/Wide, AIT-2 Ultra SCSI
    Data CompressionAdvanced Lossless Data Compression (ALDC)
    CapacityAIT-1 170 m tape 25 GB (native), 65 GB (compressed**)
    AIT-1 230m tape 35 GB (native), 91 GB (compressed**)
    AIT-2 170m tape 36 GB (native), 94 GB (compressed**)
    AIT-2 230m tape 50 GB (native), 130 GB (compressed**)
    Sustained Transfer RateAIT-1 3MB/s (native), 7.8 MB/s (compressed**)
    AIT-2 6MB/s (native), 15.6 MB/s ( compressed**)
    Average Media Load Time10 seconds, with Memory in Cartridge (MIC)
    Search SpeedAIT-1 122 inches/s, with Memory in Cartridge (MIC)
    AIT-2 160 inches/s, with Memory in Cartridge (MIC)
    Rewind SpeedAIT-1 122 inches/s
    AIT-2 160 inches/s
    Average Media Uses30,000 end-to-end passes
    Operating Temperature40°F to 104°F (5°C to 40°C)
    Dimensions (WxHxD) 8.3" x 2.5" x 11.5"
    211mm x 64mm x 292mm
    **2.6:1 compression