Steganography Essay, Research Paper
While Encryption is noticeable and a mark for inquiries by the authorities
every bit good as hackers, Steganography takes it one measure further and hides the
message within an encrypted message or other mediums ; such as images, doing it
virtually impossible to observe. It is a method related to the art of concealing a
secret message within a larger one in such a manner that the unwanted individual can non
do out the presence or contents of the concealed message being sent. It can be
hidden in a image or a sound file.
Most communicating channels like telephone lines and wireless broadcasts
transmit signals, which are ever followed by some sort of, noise. This noise
can be replaced by a secret signal that has been changed into a signifier that is non
noticeable from noise without cognition of a secret key and this manner, the secret
signal can be transmitted undetectable. [ 1 ]
A. Purpose of this paper
The intent of this paper is to present cryptography by explicating what it
is and how it works in concurrence with cryptanalysis ; supply a brief history ;
note on the types of package plans available and how effectual they are.
First, I will specify shorthand, along with cryptanalysis and digital
watermarking. I will besides discourse the differences between the two. Second, I
will discourse briefly the history of cryptography. Finally, I will reexamine
several different package applications available that provide cryptography,
how they are implemented and discourse any failures that may happen.
I will reexamine the subjects, which were discussed and give my personal sentiment
on a peculiar package plans that I tried out.
Cryptography comes from the Grecian word Steganos significance covered or secret,
fundamentally concealed authorship. Steganography is a non-cryptographic technique for
concealing informations in the natural noise constituent of some other signal. Cryptography
merely takes one piece of information and hides it within another. It uses
computing machine files ( images, sounds recordings, even discs ) which contain fresh or
undistinguished countries of informations. Invisible inks, microdots, character agreement,
digital signatures, covert channels, and spread spectrum communications besides use
Steganography. Steganography takes advantage of these countries, replacing them with
information ( encrypted mail, for case ) . The least important spots ( LSBs ) of
most digitized signals ; music or images for case ; are indiscriminately distributed.
You can alter these spots to anything you like without perceptibly altering the
music or images.
Cryptanalysis disguises the text of the message but doesn? t hide the fact
that it is making so. PGP ( Pretty Good Privacy ) , a really strong cryptographic
tool. Its popularity doesn & # 8217 ; t root from the fact that cipher knows how to interrupt
the system other than by a brute-force onslaught ( which is a requirement for any
good cryptosystem ) . PGP became popular because it is highly good designed,
fast, and has an first-class cardinal direction. There are many cryptanalytic
algorithms every bit strong as the one used in PGP, but PGP & # 8217 ; s popularity and free
handiness made it a de facto criterion for secure electronic communications
all over the universe. [ 2 ]
Digital watermarking which is a particular technique of making unseeable
digital Markss in images and audio files that carry copyright information. These
Markss can be detected by particular plans that can deduce a batch of utile
information from the water line: when the file was created, who holds the
right of first publication, how to reach the writer etc. As you know dozenss of copyrighted
stuffs are reproduced, i.e. stolen on the Net every twenty-four hours so this engineering
might be utile if you are a interior decorator.
Cryptography day of the months back to ancient Greece. During ancient Grecian wars, if a
solder needed to advise his leader that he had information on enemies be aftering
to assail at a certain topographic point and clip, he would take a clean tablet compose the
message so cover the tablet with wax. This was a manner to hide the
information as he passed through reviews. [ 3 ]
Another manner they used to direct concealed messages was to shave the courier? s
caput so tattoo the information. Once his hair had grown plenty to cover the
message, he was so sent on his manner to present the message. Of class, he had
to hold his hair shaved once more for the message to be revealed so allow his hair
During World War II, the Germans developed the microdot. A secret message was
photographically reduced to the size of a period, and affixed as the point for the
missive & # 8216 ; i & # 8217 ; or other punctuation on a paper incorporating a written message.
Microdots permitted the transmittal of big sums of printed informations, including
proficient drawings, and the fact of the transmittal was efficaciously hidden.
Another signifier of concealment
information was utilizing Null cyphers ( unencrypted
messages ) . The existent message is “ camouflaged ” in an guiltless sounding
message. Due to the “ sound ” of many unfastened coded messages, mail filters
detected the fishy communications. However “ guiltless ” messages were
allowed to flux through. An illustration of a message incorporating such a nothing cypher
News Eight Weather: Tonight increasing snow.
Unexpected precipitation clutters eastern towns. Be
highly cautious and use snowtires particularly heading
E. The main roads are wittingly slippy. Highway
emptying is suspected. Police study exigency
state of affairss in business district stoping near Tuesday.
By taking the first missive in each word, the undermentioned message can be
Newt is disquieted because he thinks he is President.
The undermentioned message was really sent by a German Spy in WWII [ Kahn67 ] :
Apparently impersonal & # 8217 ; s protest is exhaustively discounted
and ignored. Isman difficult hit. Blockade issue affects
stalking-horse for trade stoppage on by merchandises, chuck outing suets and
Taking the 2nd missive in each word the undermentioned message emerges:
Pershing canvass from NY June 1.
Recently, Margaret Thatcher was so annoyed with legion imperativeness leaks of
cabinet paperss, she had the word processors programmed to encode their
individuality in the word spacing, so that disloyal curates could be traced. [ 4 ]
Three types of stegonagraphic package bundles were evaluated by Neil
Johnson and Sushil Jajodia ( writers of Researching Cryptography: Sing the
Unseen ) on their restrictions and flexibleness. [ 5 ] They are StegoDos, White Noise
Storm and S-Tools for Windows.
StegoDos is a share-ware plan, which can be downloaded for free off the
cyberspace ( hypertext transfer protocol: //www.demcom.com ) . Its restriction is that it merely works with 320
ten 200-pixel images with 256 colourss. Using a Renoir picture, they tried to
infix a exposure of the Russian strategic bomber base ( hypertext transfer protocol: //edcwww.cr.usgs.gov/dclass ) .
It could non be used because of size limitations. They were able to utilize the
package in the Shakespeare image one time it was cropped and fitted into the 320 ten
200 pixel image. There was some deformation to the image but non really noticeable.
StegoDos uses LSBs ( Least Significant Bits ) to conceal it? s messages. It is the
less successful tool of the three tested.
White Noise Storm is a DOS application and is really effectual. It uses the LSB
attack and applies this to IBM Paintbrush ( PCX ) files. They were able to implant
the Russian strategic bomber base into the Renoir picture with no debasement
to the image. But, there were jobs due to resound intervention in the
unity of the image, which altered the colour pallet well in the
Renoir picture. The chief disadvantage of this encoding method is the loss of
many spots that can be used to keep information. [ 5 ]
The last package evaluated was S-Tools for Window. This freeware plan
Lashkar-e-Taibas you hide files of any type in.gif and.bmp images every bit good as in.wav
sounds. Furthermore, S-Tools is really a steganographic and cryptanalytic
merchandise in one, because the file to be hidden is encrypted utilizing one of the
symmetric cardinal algorithms: Triple DES and IDEA are really unafraid as of today.
Another good cryptography merchandise is Steganos for Windows 95. It has about
the same maps as S-Tools, but applies a different algorithm ( HWY1 ) and is
able to conceal informations in.bmp and.wav files every bit good as in field text and HTML files
in a really cagey manner. Steganos merely adds a certain figure of extra infinites
at the terminal of each text line. Steganos besides adds an option of directing files from
your difficult thrust to the shredder, which makes it impossible to retrieve them.
In decision, I gave a brief definition of cryptography every bit good as
cryptanalysis and digital watermarking. Following, I went into a small history about
Cryptography and where it originated. Finally, I discussed some of the package
that is available, what executions were used and noted any restrictions with
those package plans.
Steganography is much powerful tool when used in concurrence with
cryptanalysis because it adds another bed of protection to an encrypted file.
Commercial applications of cryptography, digital watermarking and digital
fingerprinting is now in usage to track the right of first publication and ownership of electronic
media. [ 5 ]
[ 1 ] Markus Kuhn, 1995
hypertext transfer protocol: //www.iks-jena.de/mitarb/lutz/security/stegano.html
[ 2 ] Introduction to PGP
hypertext transfer protocol: //sun1.bham.ac.uk/N.M.Queen/pgp/pgp.html
[ 3 ] Mr. Byte, Steganography, 1997-1999
hypertext transfer protocol: //www.tamos.com/privacy/steganoen.htm
[ 4 ] Anderson, Ross J. , Petitcolas, Fabien A.P. , On The Limits of
16 [ 4 ] 474-481, May 1998
[ 5 ] Johnson, Neil F. , Steganography, 26-34
hypertext transfer protocol: //www.jjtc.com/stegdoc/