In this smart age, smart gadgets with internet connectivity have become a necessity. While enjoying these facilities, one must count the security of their private or confidential information. With due time, a lot of cryptographic methods have been developed for enforcing security. On the other hand, with the advancement of technologies, the intruders and hackers have also developed their skills and tools. Therefore, many times we fail to protect our information. To get rid of this situation, the developers have to focus on some other method besides cryptography. Steganography can be considered as the solution to overcome this problem, as it is the technique which conceals the existence of any secret information in a usual media file. Moreover, inclusion of biometric with steganography enhances the security level, as biometric systems are dominating the field of authentication. Here, various techniques of steganography, biometrics, and steganography using biometrics will be discussed. Finally, the present scenario of steganography using biometrics will be demonstrated.
TopBackground
Steganography is a prehistorical practice. From the ancient times, steganography has been using to provide security to the confidential information. Italian mathematician Jerome Cardan reinvented Chinese ancient secret writing method. In that method two parties share a paper mask with holes and after that fill up the blank spaces. The final message appears as an innocuous text. Many secret writing techniques were invented during World War II, such as null cipher, microdot, invisible ink, etc. In the5th century, BC Hiatus wanted to send some message to his friend secretly. He shaved one of the trusted slave’s head and tattooed a message on it. The slave was sent after his hair grew back. During World War II, Morse codes were encoded in pictures, like long Blades of grass indicate dashes and dots were indicated by short blade.
The word biometrics is also originated from Greek word “Bio” which means life and “metric” means measure. Biometric define the measurement of statistical analysis of people’s physical and behavioral characteristics. This is mainly used for authentication, access control, identification. Nowadays, authentication tool/machine developers start to prefer biometrics characteristics as identification or authentication measure rather than passwords, smart card, etc. Because biometrics is a property which can defines or identify “who are you.” Various biometric characteristics are being used by different authentication machine such as palm geometry, fingerprints, iris, face, skin, etc.
Physical characteristics are related to the feature of the body, such as palm veins, retina, face recognition, DNA, fingerprint, hand geometry, etc. On the other hand, the behavioral characteristic is related to the behavior of a person. It includes signature, voice, gait, typing speed, handwriting, etc. Biometric gets the preference to be a reliable authentication measure than a password, smart card, etc. because biometric characteristics are virtually impossible to steal. Therefore, biometric starts dominating the field of authentication. We can observe the large application of biometric in regular life, e.g. Bank employees use Thumbprint to login into their system, in many universities, offices use biometric punching machine where the biometric feature of employees is used to keep the attendance.
Now, if we focus on the steganography using biometrics, it can be done in two ways, one hides your biometric information in some cover file, and another is the reserve one, i.e., biometric information will carry some secret information. Here a brief discussion related to these two mentioned types are presented.