| 1.0 IntroductionSteganography is one of the oldest | | | | of a system should not rely on the on its method |
| arts that people have always wanted to have | | | | of operation being unknown to the enemy, but |
| since they started communicating with each | | | | rather on the choice of a secret key.1.1 |
| other, but sadly the least researched. Most people | | | | BackgroundIn recent years there has been an |
| study steganography either as academic discipline | | | | exciting convergence of information protection |
| or out of curiosity and I belong to the latter | | | | technologies and the main emphasis is information |
| camp. Although steganography is used in military | | | | hiding as oppose to encryption. The two big policy |
| and commercial circuits the level of application and | | | | issues of copyright protection and state |
| understanding is very low.The term | | | | surveillance motivated this development. The |
| steganography as well cryptography was derived | | | | more information that is placed on the Internet or |
| from the Greek language. The prefix crypto | | | | public media, the more the owner of the |
| comes from the Greek word kryptos, which | | | | information need to protect themselves from |
| means hidden or secret. The suffix graphy was | | | | theft and abuse. The entertainment industry is |
| derived from graphia, which means writing. | | | | particularly very nervous due to the ease at |
| Cryptography is essentially the art of secret | | | | which exact copies of digital music and video can |
| writing and the goal is to maintain the secrecy of | | | | be made. The way forward is to embrace |
| the message even if it is visible. Steganography is | | | | advance technology to protect investment rather |
| also a form of writing (concealed writing). The | | | | than oppose it. Part of the solution may be a |
| Greek word steganos means unseen or hidden. | | | | change in the sale process of music and video; |
| Steganography is a form of hidden | | | | one mechanism is copyright marking (hiding |
| communication, it should not be seen as a | | | | notices and serial numbers in a way that would be |
| replacement for cryptography but rather as a | | | | difficult for pirates to remove). Systems and |
| complement to it. Steganography, although closely | | | | techniques that can uncover hidden information will |
| related to cryptography, is different. The goal of | | | | be useful in computer forensics and digital traffic |
| cryptography is to conceal the content of a | | | | analysis. Understanding the limitations of current |
| message, while the goal of steganography is to | | | | techniques can help develop more robust |
| conceal the existence of a message. However, | | | | techniques. The principal focus is hiding information |
| these two techniques can be combined | | | | or at least stopping other people from hiding |
| effectively by first encrypting the secret | | | | information.2.0 SteganographySteganographic |
| message before embedding in a cover data. | | | | techniques have been used since World War I and |
| Concealing the transmission of encrypted | | | | World War II, Chemicals were developed and |
| messages enhances their overall security since | | | | used as secret inks that become visible when |
| outsiders are unaware of the | | | | brought in contact with other chemicals. A brief |
| communication.Encrypted data can attract the | | | | history of steganography would give us a valuable |
| attention of hackers and investigators through its | | | | background.2.1 HistoryGreek historian Herodotus |
| mere existence, however if concealed, no | | | | recorded the earliest records of steganography. |
| attempt would be made to break the code or to | | | | When Histiaeus had to send a secret message to |
| obtain the secret key. Steganographic methods | | | | his son-in-law, he shaved the head of a slave and |
| primarily use image or audio files to hide | | | | tattooed a message, he waited till the hair had |
| encrypted data, such techniques conceal | | | | grown before dispatching him in order to avoid |
| information in the least significant bits of the | | | | detection. Another Greek history was when |
| carrier medium, which serves as a hiding place. It | | | | Demeratus scraped the wax off tablets and |
| is important that the carrier medium does not | | | | wrote messages on the underlying wood he then |
| lose its appearance after the embedding | | | | covered the wood with wax again to conceal the |
| process.Another technique similar to | | | | message. The tablets appear to be blank and |
| steganography is watermarking, the goal of | | | | unused when inspected.Invisible ink has always |
| watermarking is to mark an image or sound file | | | | been a popular method of steganography. Ancient |
| to the owner by making elusive modifications to | | | | Romans wrote between lines using invisible inks |
| the file. These modifications should not be | | | | made from substances like milk, urine and fruit |
| noticeable but rather, very robust; nobody should | | | | juices. When it is heated, the invisible ink would |
| be able to remove an existing mark or mark an | | | | darken and become legible.Gaspari Schotti wrote |
| already marked file as belonging to him. This | | | | the earliest book on steganography in 1665 called |
| technique is of great interest to the | | | | Steganographica. A major development in the field |
| entertainment industry because it gives an | | | | occurred in 1883 with the publication of Auguste |
| efficient way to determine if a file was illegally | | | | Kerckhoffs cryptographie militaire. Although the |
| downloaded from the web or rightfully | | | | work was mostly on cryptography, it provides |
| purchased.A good steganography system should | | | | valuable principle in the design of new |
| fulfil the same requirements posed by the | | | | steganographic systems [SEL03].2. |
| Kerckhoff principle in cryptography that security | | | | |