Appendix D.     SCSI and QIC - any relations ?


        Principally, the terms SCSI and QIC have (nearly) nothing to
        do with each other. However, there are some contact points.
        QIC stands for "Quarter Inch Committee" and originally meant a
        non-profit organization that was formed from tape drive and
        tape cartridge vendors to get exchange standards for tapes.

        The QIC committee and its members since then develop, approve
        and promote the various QIC standards. The numbers are somewhat
        chaotic - they somewhat seem to come out "by the numbers".
        QIC defines tape drive interfaces like SCSI, Floppy-controller
        interfaces, QIC-02/36 and tape formats like QIC-40, 80, 150 ...
        Let's try some cleaning up...

        Tape drive interface standards:

        QIC-02        : a somewhat "intelligent" hardware interface,
        QIC-36        : basic hardware interface, simpler than QIC-02
        QIC-104/11    : mainly describes SCSI-1 as tape interface
        QIC-107       : Commands and timing for QIC-80 drives
        QIC-117       : the "floppy tape" interface for QIC-80 streamers
        QIC-121       : like QIC 104, but based on SCSI-2

        A lot of the older QIC-02 interfaces are basically QIC-36 drives
        with an additional QIC-02 bridge controller. Some of these bridge
        controllers can be replaced with SCSI bridge controllers like the
        Emulex MT-02 or Adaptec ACB-3530.

        QIC tape formats:

        QIC-ID       Tape        Storage     Tracks      Length
                                 (MB)                    (FT.)
          11         300XLP        45          4           450
          24         DC600A        60          9           600
          40         DC2000        40         20           205
                     DC2060        60         20           307.5
          80         DC2080        80         32           205
                     DC2120       120         32           307.5
         120         DC600A       125         15           600
         150         DC6150       150         18           600
                     DC6250       250         18          1020
         525         DC6320       320         24           600
                     DC6525       525         24          1000
        1000    Magnus 9100      1000         32            ?
        1350           9135      1350         36            ?

        Most formats offer eXtended Length (XL) tapes that give higher
        capacity, for example the 250MB DC6250 tapes for QIC-150 drives.
        Also, there is a nuisance in the industry to call the QIC-80
        tapes with XL tapes (120MB) "250 MB" tapes. This works only
        with the compression built into the backup _software_.
        Keep this in mind if you compare tape drives with different
        technologies. The only company I know that uses a similar
        approach is Colorado with their PowerTape drives. They can
        compared by basically halving their capacity and look for the
        nearest capacity standard.


        QIC has become a company (Quarter Inch Compatibility, Inc),
        that still defines and certifies tape standards. Now, the
        members are 3M, Sony, Gigatek, HP, Conner, Colorado Memory
        Systems, IOMega, Wangtek and Tandberg (..hope i didn't forget
        someone...).
        However, since they are a company, the "introduction rate" of
        new, mostly mini-cartridge-based tape formats and standards
        is inflationary. Lots of new formats came up, some of these
        new tape drives can even read QIC-80 tapes, but most are not
        upward compatible. Of course, these standards are incompatible
        with each other, so that you can be sure that half of these
        standards will become obsolete in their first years - seems
        that the lession is "If it's business - forget the standards".
        But we'll see - it's our responsibility to buy what we feel
        should survive and keep away from the other systems.

        Some of the new advertised Mini-standards are:

        name/format      capacity         can read

        QIC-3010          255/340 MB      QIC-40/80
        QIC-3020          500/680 MB      QIC-40/80/3010
        QIC-3040          840 MB
        QIC-3080         2000 MB
        QIC-555M          555 MB          ---
        QIC-875M          875 MB          QIC-40/80/555M
        QIC-3GB(M)       3000 MB          QIC-555M

        Usually, the QIC-3010 tape drives are advertised as "700 MB"
        - the calculation is bullsh*t, as usual: 340 MB with an XL
        tape, multiplied with 2.0 as assumed compression factor,
        "slightly" (20MB) rounded up and you get 700 MB.
        If it is called "850something", like the Conner TapeStor 850,
        it is likely modified for QIC-Wide tapes - basically an 8mm
        tape with room for a few tracks more in the usual cartridge
        shell. Backup speed is identical to the old QIC-80 drives
        - means 500 kBit/sec with usual floppy hardware, 1000 kBit/sec
        with a 2.88 MB or tape controller. This may be enough for the
        usual home or office backup at night, but keep in mind that
        formatting a tape now needs 2 hours 39 minutes with a 2.88 MB
        adapter - twice this at a 1.44 MB floppy controller. So, better
        insist on formatted cartridges <g>

        QIC-3020 is faster (up to 2 MBit/sec) and has higher capacity,
        but i'm not aware of any drive that is in the market yet - the
        Exabyte EXB-1400 is announced, but i don't know anyone with it.

        QIC-3040 is defined with 840 MByte uncompressed capacity.
        Actually, the only 3040 drive i know is Tandberg's Mini Panther
        drive - with SCSI interface, as usual with Tandberg.

        QIC-3080 has 2 GByte uncompressed capacity and is already in the
        market - Conners TSM-4000 is the first example for those drives.
        QIC-3080 comes in SCSI and in ATAPI drives, both giving adequate
        performance. However, at the moment it seems to be a bit
        difficult to find a backup software working with the ATAPI tape.


        Travan is another new label initiated by 3M, Sony, HP, Conner
        and IOMega.
        The Travan concept basically consists of new tape cartridges,
        along with slightly modified QIC-80/30xx drives to use the new,
        slightly wider cartridge. To be more attractive, a Travan tape
        drive can read QIC and QIC-Wide cartridges. 3M states the
        possibility to connect the Travan tapes to the floppy interface
        as an advantage of Travan, so i would expect drives with SCSI
        and ATAPI interfaces for the professional market later - it
        simply doesn't make sense to save gigabytes over a floppy
        interface.

        The planned formats are:
        TR-1, with 400 MByte capacity, based on QIC-80 drives,
        TR-2, a modified QIC-3010 system with 800 MByte capacity,
        TR-3, 1.6 GByte capacity with a modified QIC-3020 drive, and
        TR-4, with 4 GByte uncompressed capacity.

        Travan TR-1, TR-2 and TR-3 cartridges are "available", so to
        speak, but don't expect them at your nearest small computer
        dealer.
        If you have more than the usual trouble in finding them, the 
        bigger material suppliers of like Inmac and Misco might be 
        worth a try.

        The main reason for reaching higher capacities with standard
        magnetic concepts is the longer and wider tape. Travan uses
        8 mm tapes as QIC-Wide, and uses tape lengths from 750 feet up,
        while "standard" QIC tapes are usually under 400 feet long.

        So, to sum it up, Travan is only a slightly modified QIC-80 or
        QIC-30xx system.
