02-03-2011, 03:22 PM
presented by:
Heema Jain
[attachment=9372]
STEGANOGRAPHY -Security Through Obscurity
WHAT IS STEGANOGRAPHY?
• Steganography - \Steg`a*nog"ra*phy\,
[Greek steganos (covered or secret) + graphy (writing or drawing).]
• Steganography is the art and science of writing hidden messages in such a way that no one, apart from the sender and intended recipient, suspects the existence of the message, a form of SECURITY THROUGH OBSCURITY.
• Steganography includes the concealment of information within computer files. In digital steganography, electronic communications may include steganographic coding inside of a transport layer, such as a document file, image file, program or protocol
STEGANOGRAPHY V/S CRYPTOGRAPHY
Both are used as means to protect information .
Cryptographic techniques "scramble" messages so if intercepted, the messages cannot be understood .
Steganography,"camouflages" a message to hide its existence and make it seem "invisible" thus concealing the fact that a message is being sent altogether.
The advantage of steganography, over cryptography alone, is that messages do not attract attention to themselves or arouse suspicion. Therefore, whereas cryptography protects the contents of a message, steganography can be said to protect both messages and communicating parties.
HISTORY OF STEGANOGRAPHY
Hidden messages within wax tablets: in ancient Greece, people wrote messages on the wood, then covered it with wax upon which an innocent covering message was written.
Hidden messages on messenger's body: also used in ancient Greece. Herodutus tells the story of a message tatooed on a slave's shaved head, hidden by the growth of his hair, and exposed by shaving his head again. The message allegedly carried a warning to Greece about Persian invansion plan. This method has obvious drawbacks, such as delayed transmission while waiting for the slave's hair to grow, and the restrictions on the number and size of messages that can be encoded on one person's scalp.
The milk of thithymallus plant is dried to transparency when applied to paper but darkened to brown when subsequently heated .
In WWII, the French Resistance sent some messages written on the backs of couriers using invisible ink. Common sources for invisible inks are milk, vinegar and fruit juices.
With the advent of photography, microfilm was created as a way to store a large amount of information in a very small space. In both world wars, the Germans used "microdots" to hide information. A secret message was photographed, reduced to the size of a printed period, then pasted into an innocuous cover message, magazine, or newspaper.
MODERN STEGANOGRAPHY
Modern steganography entered the world in 1985 with the advent of the personal computer being applied to classical steganography problems.
What to hide
– Texts
– Images
– Sound
Hide or embed
– text in text/images/sound files
– image in image/sound files
– sound in sound files
Heema Jain
[attachment=9372]
STEGANOGRAPHY -Security Through Obscurity
WHAT IS STEGANOGRAPHY?
• Steganography - \Steg`a*nog"ra*phy\,
[Greek steganos (covered or secret) + graphy (writing or drawing).]
• Steganography is the art and science of writing hidden messages in such a way that no one, apart from the sender and intended recipient, suspects the existence of the message, a form of SECURITY THROUGH OBSCURITY.
• Steganography includes the concealment of information within computer files. In digital steganography, electronic communications may include steganographic coding inside of a transport layer, such as a document file, image file, program or protocol
STEGANOGRAPHY V/S CRYPTOGRAPHY
Both are used as means to protect information .
Cryptographic techniques "scramble" messages so if intercepted, the messages cannot be understood .
Steganography,"camouflages" a message to hide its existence and make it seem "invisible" thus concealing the fact that a message is being sent altogether.
The advantage of steganography, over cryptography alone, is that messages do not attract attention to themselves or arouse suspicion. Therefore, whereas cryptography protects the contents of a message, steganography can be said to protect both messages and communicating parties.
HISTORY OF STEGANOGRAPHY
Hidden messages within wax tablets: in ancient Greece, people wrote messages on the wood, then covered it with wax upon which an innocent covering message was written.
Hidden messages on messenger's body: also used in ancient Greece. Herodutus tells the story of a message tatooed on a slave's shaved head, hidden by the growth of his hair, and exposed by shaving his head again. The message allegedly carried a warning to Greece about Persian invansion plan. This method has obvious drawbacks, such as delayed transmission while waiting for the slave's hair to grow, and the restrictions on the number and size of messages that can be encoded on one person's scalp.
The milk of thithymallus plant is dried to transparency when applied to paper but darkened to brown when subsequently heated .
In WWII, the French Resistance sent some messages written on the backs of couriers using invisible ink. Common sources for invisible inks are milk, vinegar and fruit juices.
With the advent of photography, microfilm was created as a way to store a large amount of information in a very small space. In both world wars, the Germans used "microdots" to hide information. A secret message was photographed, reduced to the size of a printed period, then pasted into an innocuous cover message, magazine, or newspaper.
MODERN STEGANOGRAPHY
Modern steganography entered the world in 1985 with the advent of the personal computer being applied to classical steganography problems.
What to hide
– Texts
– Images
– Sound
Hide or embed
– text in text/images/sound files
– image in image/sound files
– sound in sound files
