Institute of Science, Bangalore, India. S. B. Balaji, M. Nikhil … · 0 0 1 01 01 1 101 0110 1 1 1...
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0 0 1 1 0 0 1 0 0 1 1 0 1 1 1 0 0 1 1 1 1 1 0 1 0 1 0 0 1 1 0 1 1 1 0 0 1 1 1 1 1 0 1 0 0 0 1 1 0 0 1 1 1 0 0 0 1 1 1 0 0 0 0 0 0 1 1 0 0 1 1 0 0 1 1 1 1 1 1 1 1 1 0 0 0 1 1 0 0 1 1 1 0 0 0 0 0 1 0 0 0 1 1 1 0 0 0 0 0 0 0 1 1 0 0 1 1 0 0 1 1 1 0 0 1 1 1 1 1 1 1 1 0 0 1 1 1 1 1 1 0 0 0 1 1 0 0 1 1 1 0 0 0 0 0 1 0 0 0 1 1 1 0 0 0 0 0 0 0 1 1 0 0 1 1 0 0 1 1 1 0 0 1 1 1 1 1 1 1 1 0 0 1 1 1 1 1 1 0 1 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 1 1 0 0 1 1 0 0 1 1 1 0 0 1 1 1 1 1 1 1 1 0 0 1 1 1 1 1 1 0 0 0 1 1 0 0 1 0 0 1 1 0 1 1 1 0 1 1 0 1 0 1 0 0 0 1 1 0 0 1 1 1 0 0 1 0 0 0 1 1 1 0 0 0 0 0 0 0 1 1 0 0 1 1 0 0 1 1 1 0 0 1 1 1 1 1 1 1 1 0 1 0 0 0 0 1 1 1 1 9 1 6 2 0 1 6 1 9 2 8 1 9 9 5 1 9 8 2 1 9 7 1 1 9 5 1 Magnetic Storage Information is stored in the 2 possible orientations of a magnetic dipole. 0 1 0 0 1 1 0 1 1 1 0 1 0 1 0 1 0 1 0 0 0 1 1 1 1 1 1 1 0 0 1 1 1 1 1 0 1 0 1 1 1 0 1 1 1 1 0 1 0 1 1 1 0 1 0 1 1 0 0 0 0 0 1 1 0 1 0 1 0 1 0 0 0 1 1 1 ARRAY OF BLOCKS CELL FLASH Each cell in flash memory stores information in terms of the amount of charge held. Charge cannot be reduced from an individual cell, an entire block has to be erased. Optical Disc Information is stored as pits and lands on a reflective layer. LAser DISK BLU-RAY Blu-ray technology has a ... blue laser. Blue light has a shorter wavelength than red, thus more information can be stocked on the same disk size. SOme Key Enabling Technologies A variety of media have arisen over the years to store information in the form of digital data. Each new generation of storage device has brought with it improvements such as an increased capacity for storage, but has also presented new challenges, which engineers have sought to overcome through innovation. Error-Correcting Codes work by adding redundancy in the form of parity symbols and can range from simple replication to the more sophisticated Reed-Solomon and LDPC codes. DNA Storage: A single gram of DNA can store 455 exabytes of data for centuries. Phase Change Memory (PCM): Heating chalcogenide shifts it between a low and high resistance state. Memristors: Change in resistance of devices depends upon charge supplied. Holographic Storage: Storing data throughout the 3D volume of the storage medium. Run-length limited coding places upper and lower limits on the number of 0’s between two successive 1’s to help synchronize and limit adjacent-symbol interference (ASI). A message with content and clarity Has gotten to be quite a rarity; T o combat the terror Of serious error, Use bits of appropriate parity. SOLOMON W. GOLOMB Partial-Response Signaling with Maximum-Likelihood Detection (PRML) technology permits denser packing of data by allowing a controller amount of ASI through proper pulse shape selection. The ASI is then handled by using a trellis-based decoder that keeps track of past symbols. Additionally, a powerful LDPC error-correcting code is used. CONTROLLED PULSE SHAPE 00 01 10 11 TRELLIS-BASED DECODER Even parity constraints 1 1 1 0 AN EXAMPLE LDPC CODE - Information is stored in the strengthening or weakening of synapses which govern signal transmission between neurons - Estimated to store between 1 terabyte and 2.5 petabytes of data! THE HUMAN BRAIN Storage technologies on the horizon Data in the cloud physically resides in storage warehouses such as the Google data center shown here. 0 0 1 1 1 1 0 0 1 0 0 1 1 1 1 1 0 0 0 0 1 0 0 1 1 1 0 0 1 0 0 1 1 0 0 1 1 1 1 0 1 1 0 1 1 1 0 1 1 0 1 0 0 0 0 1 1 0 1 0 0 1 1 0 0 1 1 0 1 0 0 0 0 0 1 0 0 0 1 1 1 0 0 1 0 0 0 0 1 1 0 0 1 1 1 1 0 0 1 1 ttps://www.cirrusinsight.com 0 0 0 0 1 1 1 1 http://www.sportsandspineortho.com 0 0 1 1 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1 1 1 1 0 0 1 0 0 1 1 1 1 1 0 0 0 0 1 0 0 1 0 0 0 0 0 0 1 1 0 0 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1 1 1 1 1 0 0 0 0 1 0 0 1 0 0 0 0 0 0 1 1 0 0 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1 1 1 Two-dimensional Coding for magnetic and optical disks. Novel techniques to handle correlated errors. 1 0 0 0 0 1 1 0 0 1 1 0 0 0 0 0 0 1 1 0 0 1 1 0 0 0 0 0 1 1 0 0 1 1 0 0 1 0 0 1 1 1 1 0 0 1 1 1 1 1 1 1 0 1 1 0 0 0 0 0 0 1 1 0 0 1 1 0 0 0 0 0 1 1 0 0 1 1 0 0 1 0 0 1 1 1 1 0 0 1 1 1 1 1 1 1 0 1 0 0 1 1 1 0 0 1 1 0 0 0 0 1 1 0 0 1 0 0 0 1 0 0 1 1 1 1 0 0 1 1 0 0 1 0 0 0 1 0 0 1 1 1 1 0 0 Rank modulation codes store data in terms of the relative charge levels in different cells. Flash Memory: Overcoming the charge leakage problem. 0 1 1 1 0 1 1 1 0 0 0 0 0 0 0 1 1 1 0 0 1 1 1 1 0 1 1 1 0 0 0 0 0 0 0 1 1 1 0 0 1 1 1 1 0 0 0 0 0 1 1 0 0 0 0 0 1 1 0 0 1 0 0 1 1 0 1 1 1 0 0 1 1 1 1 1 0 1 0 0 0 1 1 0 0 1 0 0 1 1 0 1 1 1 0 0 1 1 1 1 1 0 1 0 1 0 0 0 1 1 0 0 1 1 0 0 0 1 1 0 0 1 1 1 0 0 0 0 0 1 0 0 0 0 0 1 1 1 1 0 0 1 1 1 1 1 0 0 0 1 1 0 0 1 1 1 0 0 0 0 0 1 0 0 0 0 0 1 1 1 1 0 0 1 1 1 1 1 0 0 0 Regenerating codes minimize data download; Codes with Locality minimize no. of helper nodes. Data Centers: Efficient recovery from node failure. New technologies, Fresh challenges! many thanks to Code and Signal Design Lab, Department of Electrical Communication Engineering, Indian Institute of Science, Bangalore, India. S. B. Balaji, M. Nikhil Krishnan K. P. Prasanth, Birenjith Sasidharan Myna Vajha, P. Vijay Kumar design alesiom.ch HOW DO WE STORE INFORMATION? MAgnetic tape HARd disk drive RAM FLoppy Disk CD FLASH SSD DVD
Transcript of Institute of Science, Bangalore, India. S. B. Balaji, M. Nikhil … · 0 0 1 01 01 1 101 0110 1 1 1...
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01111010 111111 010
0 000100 00
01111010 111111
0001101010 0101011
01 0001101010 010101
1 10 011111 101 0
001101010 010101
1 10 011111 101 010 010101
1 10 011111 1010 0
0
1101011 1
000
11
10 00
0
0 010100110101111111
1
11
0 0
0
1101011 1
0
0 0001
000
11
100 00
0
0 01010011010111010 11111
1 1
11
0 011111110 0
0
1101011 1
0
0 0001
000
11
100 00
0
0 01010011010111010 11111
1 1
11
0 01111111010
0 0001
0100 00
0
0 01010011010111010 11111
1 1
11
0 011111110001101010 010101
1 101 101 010 0
0
1101011 10
01
000
11
100 00
0
0 01010011010111010 11111
1 1
11
010
000111
19
16
20
16
19
28
19
95
19
82
19
71
19
51
Magnetic StorageInformation is stored in the 2 possible orientations of a magnetic dipole.
010 0101011 101 01 010100
0
0111111110011111 101 011101111 101 011101
011000 001 101010100
0111ARRAY OF BLOCKS CELL
FLASHEach cell in flash memory stores information in terms of the amount of charge held.Charge cannot be reduced from an individual cell, an entire block has to be erased.
Optical DiscInformation is stored as pits and lands on a reflective layer.
LAser
DISK
BLU-RAYBlu-ray technology has a ... blue laser. Blue light has a shorter wavelength than red, thus more information can be stocked on the same disk size.
SOme Key EnablingTechnologies
A variety of media have arisen over the years to store information in the form of digital data. Each new generation of storage device has brought with it improvements such as an increased capacity for storage, but has also presented new challenges, which engineers have sought to overcome through innovation.
Error-Correcting Codes work by adding redundancy in the form of parity symbols and can range from simple replication to the more sophisticated Reed-Solomon and LDPC codes.
DNA Storage: A single gram of DNA can store 455 exabytes of data for centuries.
Phase Change Memory (PCM): Heating chalcogenide shifts it between a low and high resistance state.
Memristors: Change in resistance of devices depends upon charge supplied.
Holographic Storage: Storing data throughout the 3D volume of the storage medium.
Run-length limited coding places upper and lower limits on the number of 0’s between two successive 1’s to help synchronize and limit adjacent-symbol interference (ASI).
A message with content and clarityHas gotten to be quite a rarity;
To combat the terrorOf serious error,
Use bits of appropriate parity.
SOLOMON W. GOLOMB
Partial-Response Signaling with Maximum-Likelihood Detection (PRML) technology permits denser packing of data by allowing a controller amount of ASI through proper pulse shape selection. The ASI is then handled by using a trellis-based decoder that keeps track of past symbols. Additionally, a powerful LDPC error-correcting code is used.
CONTROLLEDPULSE SHAPE
00011011
TRELLIS-BASEDDECODER
Even parityconstraints
1
11
0
AN EXAMPLELDPC CODE
- Information is stored in the strengthening or weakening of synapses which govern signal transmission between neurons- Estimated to store between 1 terabyte and 2.5 petabytes of data!
THE HUMAN BRAINStorage technologieson the horizon
Data in the cloud physically resides in storage warehouses such as the Google data center shown here.
00
111 1
0010 011111 1 0 00 01010111
0010 01010011
1
101 101 11 011 01010 0 01 1
010
0
110101 101
0
0 0001000
11
101010
0 0011010 111110011
https://www.cirrusinsight.com0https://www.cirrusinsight.com00https://www.cirrusinsight.com01https://www.cirrusinsight.com1 1https://www.cirrusinsight.com1
http://www.sportsandspineortho.com0http://www.sportsandspineortho.com01http://www.sportsandspineortho.com10http://www.sportsandspineortho.com00http://www.sportsandspineortho.com
01http://www.sportsandspineortho.com1
1http://www.sportsandspineortho.com11http://www.sportsandspineortho.com1111http://www.sportsandspineortho.com1111http://www.sportsandspineortho.com11http://www.sportsandspineortho.com10
0
111 1
001
00
1111 10 00010010
0 00 0011010111010 11111
1
11
11111110
0
1111 10 00010010
0 00 0011010111010 11111
1
11
111111100111Two-dimensional Coding for magnetic and optical disks.
Novel techniques to handle correlated errors.
1
000
0110101
100
000
0110101
10 0
0
0 010100110101010 11 1
10 011111111 01
100
000
0110101
10 0
0
0 010100110101010 11 1
10 011111111 01
00111
0 011010 0 01101010001001 111 0 01101010
001001 111 00
Rank modulation codes store data in terms of the relative charge levels in different cells.
Flash Memory: Overcoming the charge leakage problem.
0
11 1 0
11 10 00 00 0 01 11010 1111 1 0
11 10 00 00 0 01 11010 1111 1 000
0011010 0
001101010 010101
1 10 011111 101 0
001101010 010101
1 10 011111 101 010 0
0
110101 1
0 0
0
1101011 1
0
0 000100 00
01111010 111111 0 0
0
1101011 1
0
0 000100 00
01111010 111111
0
00Regenerating codes minimize data download; Codes with Locality minimize no. of helper nodes.
Data Centers: Efficient recovery from node failure.
New technologies, Fresh challenges!
many thanks to Code and Signal Design Lab, Department of
Electrical Communication Engineering, Indian Institute of Science, Bangalore, India. S. B.
Balaji, M. Nikhil Krishnan K. P. Prasanth, Birenjith Sasidharan Myna Vajha, P. Vijay Kumar
designalesiom.ch
HOW DO WE STORE INFORMATION?
MAgnetic tape
HARd disk driveRAM
FLoppy Disk
CD
FLASH SSDDVD
