<ul><li>In the present world, maximum of the world business is going on using “INTERNET” </li></ul><ul><li>Consequences: </li></ul><ul><li>Security required for the data, so that no other person can access it illegally. </li></ul><ul><li>Data should be transferred accurately with out errors. </li></ul>
Two basic mechanisms for security of the data 1. CRYPTOGRAPHY 2. STEGANOGRAPHY Steganography 's intent is to hide the existence of the message, while cryptography scrambles a message so that it cannot be understood.
“ To human eyes, data usually contains known forms like images, e-mail, sounds and text. Most Internet data naturally includes gratuitous headers, too.” The above message is decoded by using steganography technique concerning certain rules, as follows… “ THE DUCK FLIES AT MIDNIGHT” HOW IS IT DECODED?.......
CONSIDER THE GIVEN DATA “ T o h uman e yes, d ata u sually c ontains k nown f orms l ike i mages, e -mail, s ounds a nd t ext. M ost I nternet d ata n aturally i ncludes g ratuitous h eaders, t oo.” Here the rule is “considering the first letters of all the words”. The decoding process is done by using the above rule. This is a simple way used in steganography.
Steganography is a means of storing information in such a way that it hides private information and even the existence of the information with in the other medium. The goal of steganography is “to hide messages inside other harmless messages in a way that does not allow any enemy to even detect that there is a second secret message present.''
<ul><li>COVER: The data that is visible to the world . </li></ul><ul><li>EMBEDDED: The data to be hidden (not visible to </li></ul><ul><li>the world) </li></ul><ul><li>3. STEGO: The data contains both cover </li></ul><ul><li>&embedded data. </li></ul><ul><li>The data may be audio or video or image…etc </li></ul><ul><li>In case of audio data the cover is also termed as host signal , where as in case of image data the cover is termed as container . The process of hiding the data is known as Embedding. </li></ul>
This technique is well known to Greeks in 500 B.C itself and efficiently used in World war2 by Germany. One example is “ A p parently n e utral's p r otest i s t h oroughly d i scounted a n d i g nored. I s man h a rd h i t. B l ockade i s sue a f fects p r etext f o r e m bargo o n b y -products, e j ecting s u ets a n d v e getable o i ls.” This is given by a German Spy Giving the secret message that “ Pershing sails from NY June 1.” In World war 2.
three basic ways to encode the data in steganography are 1.Image as a carrier 2.Pixel representation in RGB 3.Bandwidth reduced file transfer Practical implementation
It is an efficient technique for steganography, An image is used as cover for hiding the actual data. Digital images are a preferred media for hiding information due to their high capacity and low impact on visibility. Basic RGB color model, every pixel is represented by the four bytes namely Alpha, red, green, blue Alpha : degree of transparency Red : intensity of red color Green : intensity of green color Blue : intensity of blue color The alpha bit is used to carry the data, as it has no much importance in image representation.
If an image data takes six mins to transfer between two systems and a text file takes 3 mins. One can use steganography technique in order to reduce the time taking by embedding the text in the image and the total content will be transferred in six mins. Two basic algorithms used for steganography are 1.Text on Image algorithm. 2. Image on Image algorithm.
“ ATTACK” --- An attempt to detect the Stegnography messages 1.ACTIVE ATTACK 2.PASSIVE ATTACK check sum character is embedded into the actual data in order to indicate the beginning of the stego data, and how much data is tampered will not be known in this process. Audio can be detected by using a specified noise signal.
1. Steganographers need to avoid well-known images for this reason . 2. S teganographer must use caution when choosing certain data hiding techniques to avoid unusual patterns
The answer is definitely “ BIN LADEN ” The attack on 11 th September was perfectly preplanned by BIN LADEN and AL QA’IDA by communicating with the hijackers by sending the pictures and the terrorist targets by using steganography technique. (in the form of pictures of children and in sports chat rooms) The advanced tools used for this purpose by them are 1. White Noise Storm 2. S-Tools …. Efficient softwares for the steganography of voice, image, data in digitized format.
<ul><li>Internet privacy. </li></ul><ul><li>2. Secret communication between the organizations like boarder security force and defense organization. </li></ul><ul><li>3. Effective than that of cryptography . </li></ul><ul><li>4. Additional layer for security than cryptography </li></ul>
That message may be an important one like “ about the safety of a country ”
As EVERY COIN HAS TWO SIDES, This technology besides having much benefits to make the internet business very safe and transmitting the defense messages secretly, there is a threat to the society if it is used in terrorism(11 th September),in anti social events. FINALLY, “ It will be more helpful if this technology is used in the proper way. The stegnography e are seeing today is just an ice cap, we have to wait until it melts(developed fully) whether it is helpful to society or becoming threat . ”