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Introduction to Data tapes

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Brief introduction to the mechanism behind data tape technology. Meanwhile, connect with ODSI - Online Digital Solutions, UK by following the below mentioned links: ODSI Blog: www.odsi.co.uk/blog Twitter: http://bit.ly/1ai6Zwe Facebook: http://on.fb.me/1ai6Ys7 LinkedIn: http://linkd.in/18C2WE6 Google+: http://bit.ly/15s113Z Pinterest: http://bit.ly/14ia10O While connect with me at the following: LinkedIn: http://linkd.in/17yrzog Email: [email protected]

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Page 1: Introduction to Data tapes
Page 2: Introduction to Data tapes

What are Data Tapes?

Page 3: Introduction to Data tapes

“Data storage device that reads and writes data on a magnetic tape”

• Magnetic Tape

– Long and narrow strip of plastic film

– Magnetized undercoating of strip

– Various levels of magnetized data are stored on strip

• Magnetic Tape Data Storage

– Digital recording on magnetic tape to store digital information

– Commonly enclosed in cartridges and cassettes

– Tape Drive performs writing or reading of data

Page 4: Introduction to Data tapes

Digitization of Data

Page 5: Introduction to Data tapes

• Digital Recording– Digital audio and video are directly recorded on a storage device– Direct encoding of data into the stream of discrete numbers which represents:

• Changes in air pressure for audio and chroma & luminance values for video through time

• Recording Process– Recording– Playback

• Techniques to Record to Commercial Media– Digital Cassettes

• Read/write head moves quickly in order to maintain a high enough speed to keep the bits at a manageable size

– Optical Disc Recording• A laser is used to burn microscopic holes into the dye layer of the

medium• A weaker laser is used to read these signals

• Digital Information– Discrete, discontinuous representations of information or works

Page 6: Introduction to Data tapes

History of Data Tapes

Page 7: Introduction to Data tapes

• Open Reels– Wound on large (10.5 in/26.67 cm) reels – Standard for large computers

• Univac– First commercial data tape UNIVAC I - 1951. – Used in UNISERVO– Drive’s recording medium:

• A thin metal strip of 0.5 inch wide– Nickel-plated phosphor bronze

• Recording density was 128 characters per inch – Linear speed of 100 in/s

• Eight tracks:– Six data tracks– One parity track– One timing track

Page 8: Introduction to Data tapes

• IBM Formats– Used ferrous-oxide coated tape – Magnetic tape dimensions were 0.5 inch– Wound on removable reels up to 10.5 inches in diameter

– Different tape lengths were available• 1200 ft., 2400 ft. • Introduction of half inch tapes

– Tape lengths increased in 1980’s• Started using PET film

– Early half-inch tape had 7 parallel tracks of data along the length – 9 track tapes supported the new 8-bit characters

– Effective recording density increased over time • Common 7-track densities started at 200, then 556, and finally 800 cpi• 9-track tapes had densities of 800, 1600, and 6250 cpi• End of file was designated by a tape mark• End of tape by two tape marks

Page 9: Introduction to Data tapes

• DEC Tape I– 0.75in wide tape, having:

• 6 data tracks• 2 mark tracks• 2 clock tracks

– Data recorded at roughly 350 bits per inch– Durable to be used as the main storage medium for a OS – First time used file sharing system– Shoe shining – 1970’s – Slow disk drive

• DEC Tape II– DEC tape II was introduced around 1978 – Same structure but used a much smaller 0.150 in tape– Enclosed in a cartridge– The TU58 DEC tape II drive had an RS232 serial interface

• Allowed it to be used with the ordinary serial ports– Low cost floppy disk technology

• DEC tape II got obsolete

Page 10: Introduction to Data tapes

• Cartridges and Cassettes

– Cassette • An enclosure that holds two reels • Single span of magnetic tape

– Cartridge• A single reel of tape in a plastic enclosure

Page 11: Introduction to Data tapes

Technical details

Page 12: Introduction to Data tapes

• Tape Width

– Half inch

• Recording Method

– Linear

• Linear Serpentine

– Scanning

• Transverse

• Accurate

• Helical

Linear Recording

Linear Serpentine Recording

Page 13: Introduction to Data tapes

• Data Blocks

– Data is written on tape in blocks

– Important to keep up with data rate

• Data Buffer

• Modern tapes offer speed matching feature

• Sequential Access to Data

– Tape provides sequential access to data

• Takes 10s to reposition the tape head

– Hard disk performs the action in 10s of milliseconds

• Offers random access to data

Page 14: Introduction to Data tapes

• Access Time

– Tape

• Long latency for random accesses

– Alternatives available

• Indexing

• Marking blocks with a tape mark

• Data Compression

– A ratio of 2:1 is typical

– Some enterprise tape drives can encrypt data

Page 15: Introduction to Data tapes

Companies Venturing in Data Tapes

Page 16: Introduction to Data tapes

• 3M

• DEC

• Sony

• HP

• Quantum

• Storage Tek

• Maxell

• IBM

• Etc

Page 17: Introduction to Data tapes

Tape Products Available at ODSI

Page 18: Introduction to Data tapes

• 8 MM Tape

• AIT Tape

• Barcode Labels

• Cleaning Cartridges

• DDS Tape

• DLT Tape

• DTF Tape

• Enterprise Tape

• LTO Tape

• T10000 Tape

• Traven Tape

• Tape Storage Cases

• VXA Tape

• Optical Cartridges

• QIC Tape

• RDX Cartridges

• SDLT Tapes

• SLR-MLR Tapes

Page 19: Introduction to Data tapes

8MM Tapes

Page 20: Introduction to Data tapes

• Magnetic data storage

• Pioneered by Exabyte

• D8 – Abbreviation used by SONY

• Dual reels in cartridge

• First Commercial Helical Scan recording

• Backward compatibility

• 170m length can store up to 170 GB

• Enhance length of 225m length stores 250 GB

• Tape Mediums:

– Metal Particles Tape– Advanced Metal Evaporated Tape (AME)– AME with Smart Clean

Page 21: Introduction to Data tapes

Advanced Intelligent Tape (AIT)

Page 22: Introduction to Data tapes

• Developed by SONY

• Dual reels in cartridge

• Provides backward and forward compatibility

• Uses helical scanning

• S-AIT is a variant

– Wider tape in larger cartridge

– Single reel

• 25GB to 1040GB

• Technical Features:

– AME (Advanced metal evaporated)

– MIC (Memory in chip)

– R-MIC (Remote memory in cassette)

– WORM (Write once read many)

Page 23: Introduction to Data tapes

Barcode Labels

Page 24: Introduction to Data tapes

• Barcodes has adhesive backing

• Use for effective management of data tapes

• Alphanumeric coding

Page 25: Introduction to Data tapes

Cleaning Cartridges

Page 26: Introduction to Data tapes
Page 27: Introduction to Data tapes

Digital Data Storage Tapes (DDS)

Page 28: Introduction to Data tapes

• Store digital data on DAT Tape

• Tape width is 3.8mm

• Latest formats are 8mm wide

• Helical scan recording method

• Length can be increased

• 2GB to 160GB

• DAT Tape:

– Developed by SONY

– Sequential transmission of data

– Ability to record digital data at:

• Higher lower and equal sampling rate

Page 29: Introduction to Data tapes

Digital Linear Tapes (DLT)

Page 30: Introduction to Data tapes

• Magnetic tape data storage technology

• Owned by Quantum Corp.

• Linear serpentine recording

• Half-inch wide tape

• Tape material is metal particle tape (MP/AMP)

• Cartridges contain a single reel

• Reel motors controls tape speed and tension

– No capstan

• DLT includes WORM capability

• 2:1 data compression

• SDLT is a variant

Page 31: Introduction to Data tapes

Digital Tape Format (DTF)

Page 32: Introduction to Data tapes

• Magnetic tape data storage format

• Developed by Sony

• Uses a 1/2in wide tape

• Cassette with two reels

• Helical scan process

• Two sizes of tape cassettes; "S" and "L”

• Highest capacity DTF 1 media tape is 42 GB

• DTF 2 tape delivers storage capacity of 200 GB

Page 33: Introduction to Data tapes

Enterprise Tapes

Page 34: Introduction to Data tapes

• Half-inch tape technology

• Few are able to encrypt data

• Leading brands

– Sun

– Imation

– Fuji

– IBM

Page 35: Introduction to Data tapes

Linear Tape Open (LTO)

Page 36: Introduction to Data tapes

• Magnetic tape data storage

– Open standards

– Part of quantum corp.

– Developed as a replacement for DLT

– Standard form-factor goes by the name Ultrium

• LTO version 6 holds 2.5tb

– 1⁄2-inch wide tape in a single reel cartridge.

• Ultrium drive reads data:

– From a cartridge in its own generation

– From cartridges of at least the two prior generations.

• An Ultrium drive writes data:

– To a cartridge in its own generation

– To a cartridge from the immediate prior generation

Page 37: Introduction to Data tapes

Optical Cartridges

Page 38: Introduction to Data tapes

• Capable of writing and rewriting data

• Available in 130 mm and 90 mm forms

• The disc consists of a ferromagnetic material

– Sealed beneath a plastic coating

– Reliable and inexpensive medium

– Designed in rewritable and WORM formats

• Leading companies offering magneto optical cartridges:

– Sony, verbatim, IBM, HP, Sony, Philips, Imation, Maxell

Page 39: Introduction to Data tapes

Quarter Inch Cartridge (QIC)

Page 40: Introduction to Data tapes

• Magnetic tape data storage format

• Enclosed in a package of aluminum and plastic

– Holds two tape reels driven by a single belt

• The tape was originally 1⁄4-inch wide

• Length is 300 to 1,500 feet

– Motorized capstan

• Data is written linearly along the length

• Could also be written in "serpentine”

Page 41: Introduction to Data tapes

RDX Cartridges

Page 42: Introduction to Data tapes

• Features a removable hard disk cartridge

– A docking station for operating the cartridge

• The highest capacity is 1 TB

• Shock-proof 2.5-inch Serial ATA hard disk drives

Page 43: Introduction to Data tapes

SLR-MLR Tape

Page 44: Introduction to Data tapes

• Perfect backup for:

– Mid-sized servers

– Small data centers

– Workstations

• Named by Tandberg Data for its line of QIC

• The earliest SLR drive has a capacity of 250 MB

• Latest drive has a capacity of 70 GB

Page 45: Introduction to Data tapes

T10000 Tape

Page 46: Introduction to Data tapes

• Latest Oracle/Sun Storage Tek tape drive

• Used with large computer system

• Tape cartridges are 1⁄2 in (13 mm) wide

• Storage Capacity:

– T10000A has a native capacity of 500 GB

– T10000B drive support 1 TB

– T10000C tape drive stores 5 TB natively

Page 47: Introduction to Data tapes

Travan Tape

Page 48: Introduction to Data tapes

• 8 mm magnetic tape cartridge

• Developed by the 3M company

• 750 inch length

• Linear track recording technology

• Travan does not verify data after writing

• The tape is not attached to the hubs

– Wrapped and held by friction

Page 49: Introduction to Data tapes

Tape Storage Cases

Page 50: Introduction to Data tapes
Page 51: Introduction to Data tapes

VAX Tape

Page 52: Introduction to Data tapes

• “Packet technology” data format

• Helical scan technology

• 2 read heads for Each stripe

– Each stripe starts with a unique packet ID

– Ends with an ECC packet checksum

• Ensures data integrity

Page 53: Introduction to Data tapes

Thank YouTHANK YOU

Website: www.odsi.co.uk Contact: +44 (0) 203 005 9500 Email: [email protected]

Source: Wikipedia