RE: Stenography

["David Gillett" <gillettdavid () fhda edu>]

  First of all, I think you mean steGAnography -- hiding data within other
binary objects.  Stenography has to do with taking dictation in
shorthand....

There are two key issues in steganography.  One is that you want your hidden
bits to have minimal visible impact on the data you're hiding them in, and
that means using a very small fraction of the enclosing data in positions of
minimal significance -- that's why LSB was chosen in this case.  You're
proposing to use only a subset of THOSE bits, and that's fine as long as you
realize that you're sacrificing bandwidth even more than usual.
  The other issue is with confirming that when you recover the bits, you
have a real message and not just noise.  You can include a hash check or
cryptographically sign the hidden text, but either increases the number of
bits you need to hide -- see the first issue....

"Increasing the security" is not a real metric.  You're decreasing the odds
that someone will randomly stumble across and discover your hidden text, but
at the cost of bloating your storage/bandwidth requirements.  But that's
exactly the choice you made in deciding to use steganography in the first
place.

David Gillett


-----Original Message-----
From: Elmozamil () yahoo com [mailto:Elmozamil () yahoo com]
Sent: Tuesday, March 30, 2010 01:17
To: security-basics () securityfocus com
Subject: Stenography

Hi, I have a problem in stenography using LSB, I want to enhance it's
security, as you known the algorithm replace the last bit in the host byte,
I try to make space between bits like put bit in first byte and escape the
second and put in the third and so on, I want your opinion on this mechanism
or other way to do it.. Thanks.

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------------------------------------------------------------------------
Securing Apache Web Server with thawte Digital Certificate
In this guide we examine the importance of Apache-SSL and who needs an SSL certificate.  We look at how SSL works, how 
it benefits your company and how your customers can tell if a site is secure. You will find out how to test, purchase, 
install and use a thawte Digital Certificate on your Apache web server. Throughout, best practices for set-up are 
highlighted to help you ensure efficient ongoing management of your encryption keys and digital certificates.

http://www.dinclinx.com/Redirect.aspx?36;4175;25;1371;0;5;946;e13b6be442f727d1
------------------------------------------------------------------------