Computer Application-Magnetic Tape Primary Storage Vs. Secondary Storage Sequential and Direct Access Devices,Storage Organization

1. Magnetic Tape
Betsy Chacko
HOD & Assistant Professor
Department of Computer Applications
St. Mary’s College Thrissur

2. Contents
• Primary Storage Vs. Secondary Storage
• Sequential and Direct Access Devices
• Magnetic Tapes
• Storage Organization
• Type and Capacity
• Advantages
• Magnetic Tape : Today
• New Technologies Introduced
• Future of Data Storage
• Conclusion
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

3. Primary Memory
• Mandatory
• Volatile
• Expensive
• Limited Capacity
Secondary Memory
(External Memory or Auxiliary Storage)
• Huge volume
• Non Volatile
• Less Expensive
Primary Storage Vs. Secondary Storage
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

4. Sequential and Direct Access Devices
Sequential
• Sequencing through
locations
• Access time varies
according to location
• Eg : Magnetic Tape
Random
• Direct access storage
device
• Access any location at
random
• Approximately equal
access time
• Eg: Magnetic Disk,
Optical Disk
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

5. Magnetic Tapes
• Sequential
• Popular for large data sets
• Plastic ribbon usually half inch or quarter inch wide
and 50 to 2400 feet long
• Surface coated with iron oxide or chromium dioxide
• Record data by magnetization
• Tape ribbon stores in reels
• Can store and erase data
• Can read the data several times
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

6. • Continuous medium
• Record data serially
• No addressing
Inter Record Gaps – Separates recors by blank spaces
Inter Block Gaps – Separates blocks by blank spaces
Magnetic Tapes
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

7. Storage Organization
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

8. Magnetic Tape: Type and Capacity
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

9. Advantages
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

10. Magnetic Tape : Today
• Modern magnetic tape is packaged in cartridges and cassettes
• Single palm-sized cartridge
• Sony Develops Magnetic Tape Storage Technology with the
Industry's Highest Recording Areal Density of 201 Gb/in2
• 20x Greater Density Than Conventional Technologyfor Supporting
High-Capacity 330 TB Recording
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

11. Technology Introduced
New technologies used for a dramatic increase in areal density
1. an improved built-in lubricant layer
a new type of magnetic layer.
2. sputter deposition
sputtering—it produces magnetic tape with magnetic grains
that are just a few nanometres across, rather than tens or
hundreds of nanometres in the case of commercially
available tape.
3. Innovative signal-processing algorithms for the data channel
based on noise-predictive detection principles, which enable
reliable operation at a linear density of 818,000 bits per inch
with an ultra- narrow 48nm wide tunneling magneto-
resistive (TMR) reader.
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

12. 4. A set of advanced servo control technologies that when combined
enable head positioning with an accuracy of better than 7
nanometers. This combined with a 48nm wide (TMR) hard disk
drive read head enables a track density of 246,200 tracks per inch,
a 13-fold increase over a state of the art TS1155 drive.
5. A novel low friction tape head technology that permits the use of
very smooth tape media
Technology Introduced cont.
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

13. Magnetic Tape : Today
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

14. Future of Data Storage
Magnetic Tape
Why?
Disk drives are reaching their limits, but magnetic tape
just gets better and better...........
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

15. Tape storage is currently the most secure, energy
efficient and cost-effective solution for storing
enormous amounts of back-up and archival data, as
well as for new applications such as Big Data and
cloud computing.
Conclusion
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur

16. 1. Computer Fundamentals: Pradeep K. Sinha &
Priti Sinha
2. https://arstechnica.com/information-technology
3. https://www.amazon.com
References
Secondary Storage Devices,Betsy Chacko,St.Mary's College, Thrissur