Difference between pages "Academic Forensics Programs - Graduate Level" and "Encase image file format"

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==US Programs==
+
The Encase image file format is used by [[EnCase]] used to store various types of digital evidence e.g.
* California Sciences Institute
+
* disk image (physical bitstream of an acquired disk)
* [http://www.ini.cmu.edu/degrees/pgh_msin/index.html Carnegie Mellon University]
+
* volume image
* Dartmouth College
+
* memory
* George Mason University
+
* logical files
* George Washington University
+
* [http://www.jjay.cuny.edu/690.php John Jay College]
+
* [http://www.forensic.msu.edu/ Michigan State University]
+
* Naval Postgraduate School
+
* Polytechnic Institute of New York University
+
* [http://cyberforensics.purdue.edu/  Purdue University]
+
* Sam Houston State University
+
* Stevenson University
+
* Texas State University
+
* [http://ncfs.ucf.edu/ University of Central Florida]
+
* University of Massachusetts, Amherst
+
* University of New Haven
+
* [http://cs.uno.edu/research/ia.htm University of New Orleans]
+
* [http://forensics.cs.uri.edu/ University of Rhode Island]
+
* University of Texas at San Antonio
+
* Utica College [http://www.onlineuticacollege.com/programs/bachelor-degrees.asp [Online]]
+
* [http://www.cis.utulsa.edu/ Center for Information Security University of Tulsa]
+
* [http://forensics.wvu.edu/ West Virginia University]
+
  
==Europe==
 
* [http://www.cranfield.ac.uk/cds/postgraduatestudy/forensiccomputing/index.jsp Cranfield University, UK]
 
* [http://www.lit.ie/departments/IT/MSC_Computing.html Limerick Institute of Technology]
 
* [http://www.studeren.uva.nl/ma-forensic-science University of Amsterdam]
 
* University of Bradford
 
* University of East London
 
* [http://cci.ucd.ie/fcci University College Dublin]
 
* [http://www.utm.ac.mu University of Technology, Mauritius]
 
* [http://www.strath.ac.uk/science/forensicinformatics/ University of Strathclyde]
 
* [http://www.glam.ac.uk/coursedetails/685/549 University of Glamorgan, Wales, UK]
 
* [http://www.digitaleforensik.com University of Applied Sciences Albstadt-Sigmaringen, Germany], Master of Science, Digital Forensics, in cooperation with University of Mannheim and University of Tübingen, Germany
 
  
==Asia==
+
Currently there are 2 versions of the format:
* [http://www.zu.ac.ae/main/en/colleges/colleges/college_information_technology/graduate_certificate_programs/cr_invest/intro.aspx Zayed University, UAE]
+
* version 1 is (reportedly) based on [[:File:ASR Data's Expert Witness Compression Format.pdf|ASR Data's Expert Witness Compression Format]].
 +
* version 2 was introduced in EnCase 7, for which a format specification (at least for Ex01) is available, but requires registration.
  
==Australasia==
+
The libewf project indicates that the January 2012 version of the version 2 format specification, besides Lx01 not being specified, is sufficient to read the format but not complete.
* [http://www.ecu.edu.au/future-students/our-courses/browse?sq_content_src=%2BdXJsPWh0dHAlM0ElMkYlMkZ3ZWJzZXJ2aWNlcy53ZWIuZWN1LmVkdS5hdSUyRmZ1dHVyZS1zdHVkZW50cyUyRmNvdXJzZS12aWV3LnBocCUzRmlkJTNEMDAwMDAwMTQ1MSUyNmxvY2F0aW9uJTNEdG9wbGV2ZWwmYWxsPTE%3D Edith Cowan University, Perth, Western Australia ]
+
  
==Africa==
+
== Version 1 ==
* [http://www.commerce.uct.ac.za/InformationSystems/Courses/inf4016w/ University of Cape Town]
+
The media data can be stored in multiple evidence files, which are called segment files.
 +
Each segment file consist of multiple sections, which has a distinct section start definition containing a section type.
 +
Up to EnCase 5 the segment file were limited to 2 GiB, due to the internal 31-bit file offset representation. This limitation was lifted by adding a base offset value in EnCase 6.
  
==See Also==
+
 
* [http://www.aafs.org/default.asp?section_id=resources&page_id=colleges_and_universities AAFS]
+
EnCase allows to store the data compressed either using a fast or best level of the deflate compression method.
* [http://www.digitalforensicsassociation.org/formal-education/ Digital Forensics Association List]
+
EnCase 7 no longer distinguishes between fast or best compression and just provides for either uncompressed or compressed.
* [http://www.forensicfocus.com/computer-forensics-education-directory Forensics Focus List]
+
 
 +
 
 +
Besides digital evidence the evidence files, or segment files, contain a header containing case information.
 +
The case information which entails date and time of acquisition, an examiner's name, notes on the acquisition, and an optional password.
 +
* In EnCase 3 the case information header is stored in the "header" section, which is defined twice within the file and contain the same information.
 +
* As of EnCase 4 an additional "header2" section was added. The "header" section now appears only once, but the new "header2" section twice.
 +
 
 +
 
 +
The format adds error detection by storing the data with checksums (Adler32), for both the metadata as the data blocks, which are by default 64 x 512 byte sectors (32 KiB).
 +
As of EnCase 5 the number of sectors per block (chunk) can vary.
 +
EnCase 3F introduced an "error2" section that it uses to record the location and number of bad sector chunks. The way it handles the sections it can't read is that those areas are filled with zero.
 +
Then EnCase displays to the user the areas that could not be read when the image was acquired. The granularity of unreadable chunks appears to be 32K.
 +
As of EnCase 5 the granularity of unreadable chunks can vary.
 +
 
 +
 
 +
EnCase 3 can store a one-way hash of the data. For a bitstream it does so by calculating e.g. a MD5 hash of the original media data and adds a hash section to the last of the segment file.
 +
As of EnCase 6 the option to store a SHA1 hash was added.
 +
 
 +
 
 +
EnCase 5 and later have the option to store '''single files''' into the EnCase Logical Evidence File (LEF) or EWF-L01.
 +
This format changed slightly in EnCase 6 and 7.
 +
 
 +
== Version 2 ==
 +
 
 +
In EnCase 7 the EWF format was succeeded by the EnCase Evidence File Format Version 2 (EWF2-EX01 and EWF2-LX01).
 +
EWF2-EX01 is at it's lower levels a different format then EWF-E01 and provides support for:
 +
* bzip2 compression
 +
* direct encryption (AES-256) of the section data
 +
 
 +
The same features are added to the new logical evidence file format (EWF2-LX01) with the exception of encryption.
 +
EWF2-EX01, EWF2-LX01 are not backwards compatible with previous EnCase products.
 +
 
 +
== See Also ==
 +
 
 +
* [[:File:ASR Data's Expert Witness Compression Format.pdf|ASR Data's Expert Witness Compression Format]]
 +
* [[EnCase]]
 +
 
 +
== External Links ==
 +
 
 +
* [http://encase-enterprise-blog.guidancesoftware.com/2012/01/2nd-generation-encase-evidence-file.html 2nd Generation EnCase Evidence File Technical Specification now Available], Guidance Software, Jan 2012
 +
* Requires registration: [http://www.guidancesoftware.com/DocumentRegistration.aspx?did=1000018246 EnCase Evidence File Format Version 2], Guidance Software, Jan 2012
 +
* [http://code.google.com/p/libewf/downloads/detail?name=Expert%20Witness%20Compression%20Format%20%28EWF%29.pdf Expert Witness Compression Format (EWF)].
 +
* [http://code.google.com/p/libewf/downloads/detail?name=Expert%20Witness%20Compression%20Format%202%20%28EWF2%29.pdf Expert Witness Compression Format (EWF) version 2].
 +
* [http://www.cfreds.nist.gov/v2/Basic_Mac_Image.html Sample image in EnCase, iLook, and dd format] - From the [[Computer Forensic Reference Data Sets]] Project
 +
 
 +
[[Category:Forensics File Formats]]

Revision as of 00:52, 21 July 2012

The Encase image file format is used by EnCase used to store various types of digital evidence e.g.

  • disk image (physical bitstream of an acquired disk)
  • volume image
  • memory
  • logical files


Currently there are 2 versions of the format:

The libewf project indicates that the January 2012 version of the version 2 format specification, besides Lx01 not being specified, is sufficient to read the format but not complete.

Version 1

The media data can be stored in multiple evidence files, which are called segment files. Each segment file consist of multiple sections, which has a distinct section start definition containing a section type. Up to EnCase 5 the segment file were limited to 2 GiB, due to the internal 31-bit file offset representation. This limitation was lifted by adding a base offset value in EnCase 6.


EnCase allows to store the data compressed either using a fast or best level of the deflate compression method. EnCase 7 no longer distinguishes between fast or best compression and just provides for either uncompressed or compressed.


Besides digital evidence the evidence files, or segment files, contain a header containing case information. The case information which entails date and time of acquisition, an examiner's name, notes on the acquisition, and an optional password.

  • In EnCase 3 the case information header is stored in the "header" section, which is defined twice within the file and contain the same information.
  • As of EnCase 4 an additional "header2" section was added. The "header" section now appears only once, but the new "header2" section twice.


The format adds error detection by storing the data with checksums (Adler32), for both the metadata as the data blocks, which are by default 64 x 512 byte sectors (32 KiB). As of EnCase 5 the number of sectors per block (chunk) can vary. EnCase 3F introduced an "error2" section that it uses to record the location and number of bad sector chunks. The way it handles the sections it can't read is that those areas are filled with zero. Then EnCase displays to the user the areas that could not be read when the image was acquired. The granularity of unreadable chunks appears to be 32K. As of EnCase 5 the granularity of unreadable chunks can vary.


EnCase 3 can store a one-way hash of the data. For a bitstream it does so by calculating e.g. a MD5 hash of the original media data and adds a hash section to the last of the segment file. As of EnCase 6 the option to store a SHA1 hash was added.


EnCase 5 and later have the option to store single files into the EnCase Logical Evidence File (LEF) or EWF-L01. This format changed slightly in EnCase 6 and 7.

Version 2

In EnCase 7 the EWF format was succeeded by the EnCase Evidence File Format Version 2 (EWF2-EX01 and EWF2-LX01). EWF2-EX01 is at it's lower levels a different format then EWF-E01 and provides support for:

  • bzip2 compression
  • direct encryption (AES-256) of the section data

The same features are added to the new logical evidence file format (EWF2-LX01) with the exception of encryption. EWF2-EX01, EWF2-LX01 are not backwards compatible with previous EnCase products.

See Also

External Links