Difference between pages "Talk:Carver 2.0 Planning Page" and "Solid State Drive (SSD) Forensics"

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License: have we even discussed a license yet?  Who chose it?  I'm not terribly opposed to a 3-clause BSD, but...? - [[User:RB|RB]] 00:39, 30 October 2008 (UTC)
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Solid State Drives pose a variety of interesting challenges for computer forensics. Most SSD devices are based on flash memory. Flash has two properties that complicate its use in computer storage systems:
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# Unlike normal hard drives that can be written in a single pass, flash memory is arranged in pages that must first be erased before it can be written.
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# Each flash page consists of multiple blocks. Typically block size is 512 bytes and page size is 2KiB, 4KiB, or larger.
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# Each page can be erased and rewritten a limited number of times---typically 1000 to 10,000. (Hard drive sectors, in contrast, can be rewritten millions of times or more.)
  
[[User:Joachim Metz|Joachim]] I prefer the LPGL it's restricts the usage of the code somewhat more. When its integrated in other (closed source) tooling which is published, they must publish that the tool uses this code.
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To overcome these problems, SSD manufacturers have created a system for ''wear leveling''---that is, spreading the writes to flash out among different sectors. Wear leveling is typically done with a ''flash translation layer'' that maps ''logical sectors'' (or LBAs) to ''physical pages.''  Most FTLs are contained within the SSD device and are not accessible to end users.
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==Bibliography==
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<bibtex>
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@inproceedings{wei2011,
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  author = {Michael Wei and Laura M. Grupp and Frederick M. Spada and Steven Swanson},
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  title = {Reliably Erasing Data from Flash-Based Solid State Drives},
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  booktitle={FAST 2011},
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  year = 2011,
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  keywords = {erasing flash security ssd},
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  added-at = {2011-02-22T09:22:03.000+0100},
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  url={http://cseweb.ucsd.edu/users/m3wei/assets/pdf/FMS-2010-Secure-Erase.pdf},
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  biburl = {http://www.bibsonomy.org/bibtex/27c408ad559fc19f829717f485707a909/schmidt2}
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}
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</bibtex>
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<bibtex>
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@article{bell2011,
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author="Graeme B. Bell and Richard Boddington",
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title="Solid State Drives: The Beginning of the End for Current Practice in Digital Forensic Recovery?",
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journal="Journal of Digital Forensics, Security and Law",
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volume=5,
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issue=3,
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url={http://www.jdfsl.org/subscriptions/JDFSL-V5N3-Bell.pdf}
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}
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</bibtex>
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==Scott Moulton's Shmoocon 2008 Presentation ==
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Scott Moulton had a presentation at Shmoocon regarding SSD drives vs. Hard Drives.
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* [http://www.youtube.com/watch?v=l4hbdZFWGog SSD Flash Hard Drives - Shmoocon 2008 - Part 1]
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* [http://www.youtube.com/watch?v=mglEnIPnzjo SSD Flash Hard Drives - Shmoocon 2008 - Part 2]
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* [http://www.youtube.com/watch?v=3psy_d-pyNg SSD Flash Hard Drives - Shmoocon 2008 - Part 3]
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* [http://www.youtube.com/watch?v=pKeZvhDd5c4 SSD Flash Hard Drives - Shmoocon 2008 - Part 4]
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* [http://www.youtube.com/watch?v=9XMBdDypSO4 SSD Flash Hard Drives - Shmoocon 2008 - Part 5]
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* [http://www.youtube.com/watch?v=LY36SWbfQg0 SSD Flash Hard Drives - Shmoocon 2008 - Part 6]
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== SSD, wear-leveling and Windows 7 ==
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* [http://www.snia.org/events/storage-developer2009/presentations/thursday/NealChristiansen_ATA_TrimDeleteNotification_Windows7.pdf ATA Trim / Delete Notification Support in Windows 7]

Revision as of 15:12, 22 March 2011

Solid State Drives pose a variety of interesting challenges for computer forensics. Most SSD devices are based on flash memory. Flash has two properties that complicate its use in computer storage systems:

  1. Unlike normal hard drives that can be written in a single pass, flash memory is arranged in pages that must first be erased before it can be written.
  2. Each flash page consists of multiple blocks. Typically block size is 512 bytes and page size is 2KiB, 4KiB, or larger.
  3. Each page can be erased and rewritten a limited number of times---typically 1000 to 10,000. (Hard drive sectors, in contrast, can be rewritten millions of times or more.)

To overcome these problems, SSD manufacturers have created a system for wear leveling---that is, spreading the writes to flash out among different sectors. Wear leveling is typically done with a flash translation layer that maps logical sectors (or LBAs) to physical pages. Most FTLs are contained within the SSD device and are not accessible to end users.

Bibliography

Michael Wei, Laura M. Grupp, Frederick M. Spada, Steven Swanson - Reliably Erasing Data from Flash-Based Solid State Drives
FAST 2011 ,2011
http://cseweb.ucsd.edu/users/m3wei/assets/pdf/FMS-2010-Secure-Erase.pdf
Bibtex
Author : Michael Wei, Laura M. Grupp, Frederick M. Spada, Steven Swanson
Title : Reliably Erasing Data from Flash-Based Solid State Drives
In : FAST 2011 -
Address :
Date : 2011

Graeme B. Bell, Richard Boddington - Solid State Drives: The Beginning of the End for Current Practice in Digital Forensic Recovery?
Journal of Digital Forensics, Security and Law 5
http://www.jdfsl.org/subscriptions/JDFSL-V5N3-Bell.pdf
Bibtex
Author : Graeme B. Bell, Richard Boddington
Title : Solid State Drives: The Beginning of the End for Current Practice in Digital Forensic Recovery?
In : Journal of Digital Forensics, Security and Law -
Address :
Date :

Scott Moulton's Shmoocon 2008 Presentation

Scott Moulton had a presentation at Shmoocon regarding SSD drives vs. Hard Drives.

SSD, wear-leveling and Windows 7