Solution Guide

78 Analyze
File Signature Analysis
Every file has a file type, usually indicated by the file name’s three- or four-
letter extension. For example, a text file might have a *.txt extension, and an
image file might have a *.jpg extension. Not uncommonly, these file extensions
will have been changed to something seemingly innocuous--an image file, for
example, might be renamed with a text file extension in an attempt to mask its
pornographic contents.
However, every file also possesses a file header that includes a file type code
different from the extension, but solely indicative of a specific file type. For
example, a *.bmp file, will have the file type header code *.bm8. When the file
type header code and the file extension differ, the digital forensics analyst must
more closely examine the data.
Figure 5-1. Distributed Processing
What is Distributed Processing?
Distributed processing refers to the use of multiple processors, each with its
own memory asset, that are individually applied to a different portion of a single
computational task, and that use a message passing system to communicate
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