Introduction
Stenography is a scientific technique that allows secure communication without revealing the intended message to a third party. This form of passing messages has been used for a long period. The Greek people are among the scholars who pioneered the use of the technique. The Greeks used secret writing to pass messages from one individual or group of people to the next without letting a third party know the intended message even if such a party saw it. The term stenography was initially a direct translation of the Greek work for undisclosed writing (Silberstein-Loeb, 2009). Stenography has been passed from one generation to the next. It has found application in many areas including the military and the diplomatic communications.
Presently, stenography means any process that can lead to the hiding of messages within another object. When hidden, this message becomes unapparent to observers who see a different image or writing that does not make sense to them. The earliest application of this form of communication and information protection includes the First and Second World Wars where the armed forces used stenography extensively to pass messages to their colleagues behind battle lines and/or resistance within a given country and region. This paper examines the meaning of stenography, its history, and its current use. Besides, it shows how it differs from watermarking. It also examines the available stenography detectors and the areas where they are applied.
Literature Review
Several authors have looked at the history of stenography and its use. Most of them have discussed its relevance in the military and in the current information age. Some of the earliest writers who wrote about Stenography as an art in communication include Johannes Trithemius who lived in Germany in the in the late 15th century (Judge, 2001). According to Judge (2001), Johannes described the art of writing and communicating with the spirits. In his work, Trithemius is said to have described several ways of hiding messages in writing (Judge, 2001). After the analysis of Johannes’ works, researchers found that there were hidden messages in the works. Dr. Ernst Paper as one of the researchers managed to get the hidden messages (Judge, 2001).
Many other works of art were meant to hide the intended messages to the audience, including the works of Mary Queen of Scots (Judge, 2001). Some of the normal writing materials that have been examined in the past also contain significant forms of stenography. According to Judge (2001), examples of these works include the Peruvian Geoglyphs that are visible from the air. Some of the methods that were traditionally used to pass secret messages include the inscription of messages on silk and rolling it into a ball that was then be swallowed by the messengers (Judge, 2001).
In the Second World War, the Nazis developed microdots that took the form of high-magnification microfilm chips. According to Judge (2001), the chips were used to pass messages to different individuals in the war. Judge (2001) also states that the Nazis used other forms of passing information secretly, including the use of invisible ink and null ciphers. During the same war, the Germans together with their enemies used different methods of coding information that could be passed to soldiers in the battlefield. Soldiers passed messages using the dial arrangement on their wristwatches while others passed these secret messages via games that were played on the mail (Tsou, Lai, Sin, & Cheung, 2006). The Unites States Marines also used secret codes during the Second World War. According to Miyako (2002), the marines used Najavo code talkers whose codes were sent to the intended recipients in their coded form.
Some of the inventors of different types of coding messages worked in the military, with this strategy being the institution that applied significant coding when passing messages. For example, Girolama Cardano invented the use of a paper grill that had holes punctured on it. When placed on another paper with plain text, a person could get the message by reading the letters that appeared on the holes. This technique later came to be known as the ‘Cardano Grill’ after its inventor (Downey, 2006).
The American Civil War was another war that was marked by the use of secret codes, which communicated coded messages to the slaves who escaped from their masters (Downey, 2006). Some people who were held hostage in some parts of the world have also used stenography to communicate a form of coded messages to the outer world. According to Judge (2001), an example of this method is the crew of the U.S.S. Pueblo that managed to spell a word to the outside world in one of the photos that they had taken while in captivity.
The Vietnam War was also characterized by the use of stenography as a form of passing secret messages (Downey, 2006). The Morse code is one of the codes that were used in the Vietnam War to communicate secretly coded messages. The prisoners of war could communicate to the outside world by blinking in a manner that was meant to communicate to them. A tap code was also used in stenography in war where prisoners used a sequence of taps to communicate specific messages to each other (Downey, 2006).
With the invention of computers, stenography became digital where computer experts developed messages that were encoded for transfer to other individuals. Digital technologies such as movie images, text files, still images, and audio formats are some of the most commonly used forms of digital stenography (Mazurczyk, 2013). The 2001 attacks in the United States of America were followed by a growing concern that the Al Qaeda network was using coded images to communicate (Mazurczyk, 2013). The suspicion was that this network was coding information on pornographic photos on the internet, with these photos being used to give instructions to the fighters in the country.
The television broadcasts made by Osama Bin Laden as the leader of this network were also thought to contain hidden messages that were meant to give signals to the followers in many parts of the world (Wilson, 2004). Researchers feared that the televised broadcasts that Osama made to the many networks consisted of coded messages in the audio portion of the messages. The background for these broadcasts was also feared to harbor coded messages, although they were not found after analysis of the videos (Mazurczyk, 2013). The possibility of terrorists using coded messages to command their fighters is distressing for security forces throughout the world.
Digital watermarks are an example of the use of digital stenography. They have been proven useful in the past. Images, movies, music, and other items can be imprinted with digital watermarks (Judge, 2001). According to Judge (2001), digital watermarks can vary in type, with some being fragile while others are robust. Another classification for these watermarks includes public vs. private and the classification of visible vs. invisible watermarks (Judge, 2001). Apart from the application of digital watermarking on the above areas, this concept is also applicable in other types of media platforms that are not necessarily digitalized. According to Wilson (2004), digital watermarks may be used in printed images.
While using digital watermarks on printed images, a half-tone screen is generated with a key image (Judge, 2001). The key image only appears after the screen is superimposed on the image (Judge, 2001). Another technique that is applied in digital stenography is the use of stochastic screens, which are almost similar to the above use of stenographic methods to code information within a text or a photo. Different methods have been invented to overcome each of the stenographic techniques that are applied in the digital world. Attackers have been known to use sophisticated methods of attacking the digital watermarks. Judge (2001) categorizes these attacks as being, “additive noise, filtering, cropping, compression, rotation and scaling, statistical averaging, multiple watermarking, and attacks at other levels” (p. 7).
Apart from the digital watermarking that is a significant application of stenography in the current world, several physical watermarking practices are used to offer physical security. The Second World War saw an increased use of august microdots, which were mainly being used by the Nazis in the war (Wilson, 2004). This stenographic technique is still being advocated for as a simple security measure for marking equipment (Wilson, 2004). With the increasing cases of theft all over the world, this simple technique is aimed at identifying the stolen goods for return to their rightful owners. This program has also led to the emergence of several firms that offer the microdots at a cost, with the industry growing at a fast rate.
Supermarkets and retail outlets are some of the areas that have used stenography as a form of security and/or to pass certain forms of messages to the intended parties. Most of the retail outlets operate an Electronic Article Surveillance (EAS) system where special tags are placed on merchandise in the retail outlets (Downey, 2006). For the merchandise to be allowed out of the retail outlet, the buyer has to pay for the merchandise first or make special arrangements so that the message may be deleted. If this message is not deleted, just as in the case where an individual takes the merchandise without paying, the tags are detected by the scanning mechanisms at the storefront. This method gives a signal that the merchandise has not been paid for (Downey, 2006).
Some other examples of stenographic techniques are applied in entertainment, with the main example being the phonographic records (Judge, 2001). Over the past several years, different individuals have stated that phonographs may contain satanic messages that are encoded in the phonographs (Wilson, 2004). When played backwards, Wilson (2004) reveals that the phonographs may contain satanic messages. Although this assumption has largely been criticized and described as being erroneous, researchers agree that the present level of technology can allow the production of coded messages using the technique (Judge, 2001).
Subliminal suggestions dominated the US theatres in the 1950s. According to Wilson (2004), this stenographic technique can be applied in passing coded messages. As the public was busy having fun in the theatres with the subliminal messages being passed, the Central Intelligence Agency is said to have been working behind the scenes on a research on how subliminal suggestions could be applied in passing coded messages (Judge, 2001). According to Judge (2001), “Subliminal suggestions may range from advertisements (either blatant suggestion to images/messages perceived by various groups as having a particular meaning) to modern subliminal suggestion programs such as those available from Inner Talk” (p. 8).
Judge (2001) evaluates the use of photo tiling to form images as a potential stenographic technique. He states that this method can be used to hide information in photos that are used to create the images (Judge, 2001). Another potential form of stenographic technique that Judge (2001) describes is the conversion of image files into ASCII art. The conversion of images into ASCII test images is said to be a potential stenographic technique that can be used to send information from one individual to the next (Judge, 2001). Judge (2001) estimates that an individual can arrange letters from one part of the image to form a coded message that can be used to advocate secretly for something.
Judge (2001) lists a variety of methods that can be used as stenographic techniques. Some of these techniques include, “holography technology, infrared (e.g. programmable IR hand controls for computers, pagers, colored glasses that filter all but intended wavelengths to make hidden messages visible, and DNA message hiding” (Judge, 2001, p. 10). Stenographic techniques can also be as simple as the use of Jargon and/or the use of HTML code over the internet. In the past, some of the devices that could have been used to pass coded information include the disk floppies and hard drives whose blank areas contained coded information (Judge, 2001).
Some other researchers have attempted to describe the art of stenography and its increasing use in the computer security. Stenography allows communication without alteration of the message. However, san attacker is able to develop ways of detecting the embedded data in the communication being transmitted (Wilson, 2004). The internet has become an important tool in our daily lives by allowing the sharing of music, videos, and images (Downey, 2006). This growth on the internet has enabled the expansion of digital imagery. Through the internet, some individuals have been able to make copyright materials that are distributed without the owners’ consent.
In the current era of the information age, users can exchange information from one point to the other with minimal detection from the systems in place. This has led to the growth in piracy, with the industry generating billions of dollars and leading to similar amounts in losses to the rightful owners. Watermarking allows the prosecution of violators. Original copies are made with a watermark that cannot be copied into the other pirated copies. The music industry is one of the areas where stenographic techniques such as the ones described above are used widely. This technique has contributed to the decrease in the number of pirated music on the internet.
Detection of stenographic techniques is a major part of the business, with several organizations being tasked with this detection. The growth of terrorism in the world has seen terrorists use stenographic techniques to pass messages from one part of the globe to another in preparation for attacks. Stenography has also been used by other individuals in the society for the wrong reasons such as in the promotion of pedophilia (Mazurczyk, 2013). Detection of stenographic data has become a key part of law enforcement according to Mazurczyk (2013). The science of detecting stenographic messages is referred to as steganalysis. According to Mazurczyk (2013), this detection may be passive or active. There are specialized detectors that are used to detect the stenographic messages. They detect the present watermark.
Some of the places where defection of stenography is applied include the CIA and other security organizations in the United States. The detectors check for a variety of formats that are hidden within the stenographic texts. These agencies compare the original images and files against those that are presented to them. The absence of a watermark alerts the detectors that the files being analyzed are not true copies of the documents or media under scrutiny. These organizations may then prosecute the sources of these documents or the media. Some researchers have highlighted some of the detection techniques that may be applied in the detection of stenographic techniques that are used over the internet.
The attackers who are out to get the messages being communicated to other parts of the world also do the detection of stenographic techniques. Such attackers use several forms of attacks to detect the information presented in the stenographic form. The attacks may be simple or take the form of robustness (Wilson, 2004). The attackers use these methods to detect the watermarks in an effort to alter them to their advantage, including the provision of information regarding the images and objects being detected. The detectors are also present in retail stores where they detect the hidden messages on the merchandise to prevent any form of stealing. This strategy has been instrumental in ensuring that the cases of theft in these areas are reduced.
Discussion
The analysis of the above literature proves that stenography is not a new form of security, although it has undergone a series of transformations. Most researchers agree that stenography is an art and science of secret communication where an individual passes a message to another without having to worry about third parties. The application of stenography is not new. Pioneers of this concept used it for several purposes. Some of them used stenography as a form of resistance during times of war while others used it to make fun of other people (Coşkun, Akar, & Çetin, 2013). Despite the different uses of stenography, different techniques have been developed for application in stenography.
Traditionally, stenography was applied in physical communication where an individual could pass information in a hidden form from one area to another. There had to be a secret method for the two parties to interpret the messages that they were communicating to each other. This communication had to be a secret that could not be shared with other individuals (Gardey, 2001). Researchers also state that the First and Second World Wars led to increased use of stenography, with officers passing information from one area to another in simplified ways. The Nazis were some of the main users of stenography in communication during the Second World Wars. Their efforts led to the war taking longer than expected.
With the development of computers, a new concept of digital stenography emerged. The internet has propelled stenography to a different level. It is currently the leading platform where stenography is applied. Researchers highlight the various techniques that are applied in digital stenography, including the watermarking technique (Downey, 2006). The internet is a significant source of copyright infringement, with many artists losing millions of dollars through the copyrighted materials. Customers can easily obtain copyright materials and send to their friends through direct links that prove too difficult for the detectors to identify.
Some of the techniques that researchers discuss as being useful in digital watermarking include the use of the binary file and the text techniques (Downey, 2006). Another technique that has been widely applied is the image technique as discussed by Condell, Curran, and Kevitt (2010). This technique has been applied in many areas and on many platforms that are viewed as being areas of security threats (Downey, 2006). Researchers state that the different techniques used have different levels of efficacy and strength. Some of the methods are more secure in relation to others. The various evaluated literatures did not differentiate stenography from watermarking. However, Wilson (2004) confirms that watermarking is a form of stenography that was originally applied to the physical data and files.
Legitimate uses of stenography that are evident from the literature review include the protection of genuine works from copywriters and the passing of information from one area to another in the military. Stenography is also increasingly becoming useful in business, with retail outlets using it as a form of security. The other legitimate use of stenography is protection of consumers and provision of quality services in the retail outlets that are described above. However, some individuals have found ways of using stenography in other ways that may not necessarily be useful. Researchers state the recent attacks by terrorists in the US cities and elsewhere in the world (Downey, 2006). They believe that these terrorists and terror organizations are applying stenography to pass messages to their followers and plan for attacks (Downey, 2006).
There are several types of stenography detectors present in several arms of the government. These detectors include those that detect the watermark in copies of original music, thus allowing for detection for the copyrighted ones (Wilson, 2004). The detectors also include the Laser guided gadgets that are able to identify a series of stenographic texts and images (Wilson, 2004). Retail outlets also use detectors that allow them to detect the identification information pertaining to the merchandise. In relation to the areas where these detectors are found, researchers state that they can be found in areas where the detection of stenographic information takes place. These areas include the supermarket front areas and law agencies among other areas.
The discussed literature indicates an increasing growth in the application of stenographic techniques in security as the main area that applies them. In the next few years, the use of these techniques is likely to grow, with the main cause of growth being the increasing security threats. Different researchers have different opinions over the growth of stenographic techniques. The main area of growth is the application of stenographic techniques in the provision of security for the information being passed from one area to the next.
Analysis
The available literature provides the uses of stenographic techniques in the provision of security for the information shared over the internet. Despite these techniques offering security for the information shared over the internet, some of the processes used in stenography are still inadequate. The vulnerability of data and security systems applying stenography has been a key concern over the past few years, with attackers managing to access information that they are not supposed to have access. The attackers have developed sophisticated methods of ensuring that they are ahead of authorities and that they have exposed the existing loopholes in the stenographic systems.
There is a need for increased research into the methods of preventing attacks from malicious individuals in the process of transmitting information from one place to another. Future studies also need to address the different strategies that are in place to ensure that the employed stenographic techniques are efficient in the protection of data that is transmitted from one individual to the next. Throughout the history of stenography, various uses have been applied to protect information. Researchers need to come up with simple stenographic techniques that may be applied by ordinary individuals in the protection of information that they want to share with other individuals, or the different strategies in place for these techniques.
There is a need for future work in the area of stenography, especially where researchers need to introduce the technique in the protection of music and images from copyrights. To ensure that this happens, there is a need for increased training on the use of the stenographic techniques and the devices that are present in the field of communication. Future work is necessary where researchers need to develop new ways of ensuring the best security for data and physical documents. Training will ensure that the area is well equipped to handle many cases of attacks that have dominated the area.
Recommendations
A number of recommendations are possible in relation to the use of stenography and watermarking. The internet has led to some crimes manifesting in a strong way in relation to what was previously observed. One of these crimes is criminal communication, which occurs between criminals, thus allowing room for offenses that may be preventable. There is a need to increase the use of digital stenography on the internet, with the target being this form of crime. The other crime that is prominent over the internet is fraud. Many people have fallen victim to this crime. For this crime to be reduced, internet companies need to develop a system that is able to detect a large number of threats through the recognition of stenographic techniques that are employed in the different internet contents.
Electronic payments have revolutionized the business environment. They have led to the growth of international trade. However, cybercrime has increased the vulnerability of this form of payment, with individuals losing large amounts of money to attackers. The inception of stenography is an important aspect of preventing these forms of crime. Violators will be punished adequately. Stenographic techniques should be developed to tackle this form of crime that leads to the loss of millions of dollars every year. Authorities also need to enact legislation to control cybercrime and/or introduce tough penalties for the offenders.
The other recommendation is that due to the rising cases of violation of intellectual property rights, the governments around the world need to form an alliance that can fight copyright in different parts of the world. This move will ensure that the rights of musicians and other artists are respected and that they are allowed to make money in a fair manner. The other recommendation that can be followed to ensure that stenography and watermarking work for the benefit of artists is the provision of special rights for the artists to make works of art while using stenographic techniques that are only known to them to market their music. This move will ensure that the artists are party to the effects that are experienced in the application of these stenographic techniques.
Conclusion
In conclusion, stenography is an art and a science whose use began many centuries ago. The analysis of literature provides the definition for this term, with the consensus being that it is the communication of information in hidden form. This article has looked at the different authors who have done works on the topic and the findings that they reported. The different areas where stenography is used include in the military and in the provision of protection for works of art such as music and videos. The paper has also focused on the detection methods in use and the areas where these methods are used. Despite the gains in this field, there are still frequent attacks of the stenographic techniques. The recommendations include the increased training of individuals to counter the attackers. The use of skilled individuals, especially in the field of stenography, will guarantee attack-free interactions from any platform.
Reference List
Condell, J., Curran, K., & Kevitt, P. (2010). Digital image steganography: Survey and analysis of current methods. Signal Processing, 90(3), 727-52. Web.
Coşkun, İ., Akar, F., & Çetin, Ö. (2013). A new digital image steganography algorithm based on visible wavelength. Turkish Journal Of Electrical Engineering & Computer Sciences, 21(2), 548-564. Web.
Downey, G. (2006). Constructing “Computer-Compatible” Stenographers: The Transition to Real-Time Transcription in Courtroom Reporting. Technology & Culture, 47(1), 1. Web.
Gardey, D. (2001). Mechanizing writing and photographing the word: utopias, office work, and histories of gender and technology. History & Technology, 17(4), 319. Web.
Judge, J. (2001). Steganography: Past, Present, Future. SANS Institute, SANS Institute InfoSec Reading Room. Web.
Mazurczyk, W. (2013). VoIP Steganography and Its Detection-A Survey. ACM Computing Surveys, 46(2), 20-1. Web.
Miyako, I. (2002). Stenography and ventriloquism in late nineteenth century Japan. Language And Communication, 31(1), 181-190. Web.
Silberstein-Loeb, J. (2009). Closed Captioning: Subtitling, Stenography, and the Digital Convergence of Text with Television. Business History Review, 1(1), 199. Web.
Tsou, B. K., Lai, T. Y., Sin, K. K., & Cheung, L. L. (2006). Court Stenography-To-Text (“STT”) in Hong Kong: A Jurilinguistic Engineering Effort. International Journal Of Computer Processing Of Oriental Languages, 19(2/3), 99-107. Web.
Wilson, P. (2004). The Corpus of Jinglese: A Syntactic Profile of an Idiolectal ‘System of Stenography. Critical Survey, 16(3), 78-93. Web.