SteganographySlide 2Steganography - IntroductionSteganography- HistorySteganography Modern TechniquesSteganography Historical TechniquesHistorical Techniques ContinuedSteganography ExamplesSlide 9Conclusion Steganography and SecurityThe EndSteganographSteganographyyPresentation By Presentation By Tina A. PeabodyTina A. PeabodyITE100 T/R 0930ITE100 T/R 0930Northern Virginia Community CollegeNorthern Virginia Community College20062006SteganographySteganographyIntroductionIntroductionHistoryHistoryTechniquesTechniquesModernModernHistoricalHistoricalExamplesExamplesConclusionConclusionSteganography -Steganography - IntroductionIntroductionSteganography has recently been thrust into the international Steganography has recently been thrust into the international spotlight as a result of the War on Terror.spotlight as a result of the War on Terror.Steganography has been in existence since the dawn of written Steganography has been in existence since the dawn of written communication.communication.Steganography (meaning “covered writing”) is the art of hiding Steganography (meaning “covered writing”) is the art of hiding written communications.written communications.Steganography is the art and science of writing hidden messages in Steganography is the art and science of writing hidden messages in such a way that no one apart from the intended recipient knows of such a way that no one apart from the intended recipient knows of the existence of the message. This is in contrast to cryptography, the existence of the message. This is in contrast to cryptography, where the existence of the message itself is not disguised, but the where the existence of the message itself is not disguised, but the content is obscured.content is obscured.SteganographySteganography- History- HistoryThe word The word “Steganography“Steganography” is of Greek origin and means ” is of Greek origin and means ”covered, or ”covered, or hidden writing”.hidden writing”. It’s ancient origins can be traced back to 400 BC. It’s ancient origins can be traced back to 400 BC.Although the word Steganography is Greek, the first reported use of this Although the word Steganography is Greek, the first reported use of this practice dates back to 11practice dates back to 11thth century China. When diplomats would write century China. When diplomats would write messages on thin pieces of silk and roll it into small balls. These small balls messages on thin pieces of silk and roll it into small balls. These small balls can be easily hidden on the messenger’s person or swallowed.can be easily hidden on the messenger’s person or swallowed.http://library.thinkquest.org/27993/crypto/steg/classic1.shtmlhttp://library.thinkquest.org/27993/crypto/steg/classic1.shtmlAncient Greek ruler Histeaus, shaved the head of his most trusted slave, Ancient Greek ruler Histeaus, shaved the head of his most trusted slave, tattooed the message on his scalp, once hair grew back sent him to deliver tattooed the message on his scalp, once hair grew back sent him to deliver the message.the message.During her imprisonment Mary Queen of Scots used a combination of During her imprisonment Mary Queen of Scots used a combination of cryptography and steganography to conceal letters. Her letters were cryptography and steganography to conceal letters. Her letters were delivered to and fro by way of a beer barrel bunghole where the messages delivered to and fro by way of a beer barrel bunghole where the messages were hidden.were hidden.Bunghole is a hole bored into a barrel, bung is a large cork like object.Bunghole is a hole bored into a barrel, bung is a large cork like object.http://www.sans.org/rr/whitepapers/steganography/552.phphttp://www.sans.org/rr/whitepapers/steganography/552.phpSteganographySteganographyModern TechniquesModern TechniquesConcealing messages within the lowest bits of noisy images or sound files.Concealing messages within the lowest bits of noisy images or sound files.Concealing data within encrypted data. The data to be concealed is first Concealing data within encrypted data. The data to be concealed is first encrypted before being used to overwrite part of a much larger block of encrypted before being used to overwrite part of a much larger block of encrypted data. Examples of software that use this technique include: encrypted data. Examples of software that use this technique include: Free0TFE and TrueCrypt.Free0TFE and TrueCrypt.Modern updates to these ideas use computers to make the hidden message Modern updates to these ideas use computers to make the hidden message even less noticeable. For example, laser printers can adjust spacing of lines even less noticeable. For example, laser printers can adjust spacing of lines and characters by less than 1/300th of an inch. To hide a zero, leave a and characters by less than 1/300th of an inch. To hide a zero, leave a standard space, and to hide or leave 1/300th of an inch more than usual. standard space, and to hide or leave 1/300th of an inch more than usual. Varying the spacing over an entire documentVarying the spacing over an entire documentChaffing and winnowing (Confidentiality without Encryption) Chaffing and winnowing (Confidentiality without Encryption) Invisible inkInvisible inkNull ciphersNull ciphersConcealed messages in tampered executable files, exploiting redundancy Concealed messages in tampered executable files, exploiting redundancy ( (http://crazyboy.com/hydan/http://crazyboy.com/hydan/))Embedded pictures in video material (optionally played at slower or faster Embedded pictures in video material (optionally played at slower or faster speed)speed)SteganographySteganographyHistorical TechniquesHistorical TechniquesHidden messages in wax tablets: in ancient Greece, people wrote Hidden messages in wax tablets: in ancient Greece, people wrote messages on the wood then covered it with wax so that it looked like an messages on the wood then covered it with wax so that it looked like an ordinary, unused tablet.ordinary, unused tablet.Hidden messages on messengers body: also ancient Greece. The story told Hidden messages on messengers body: also ancient Greece. The story told of a message tattooed on a slaves head, hidden by growth of his hair, and of a message tattooed on a slaves head, hidden by growth of his hair, and exposed by shaving his head again. The message, if the story is true, exposed by shaving his