It is not surprising that a variety of techniques for protecting data have developed given the volume of data that is generated and communicated electronically in the modern world. Steganography is one method that is expanding quickly. In this tutorial we will discuss Steganography in detail.
Before we begin, these are the topics that will be discussed:
- What Is Steganography
- How Is Steganography Different from Cryptography
- Steganography Techniques
- Best Tools to Perform Steganography
What is Steganography?
Steganography is the enclosing of hidden communications in a file (photo, mp3, etc) so that only the sender and the intended receiver are aware of their presence.
Background
Steganography is the art of hiding a confidential message inside of an ordinary communication. It derives from the Greek terms steganos, which means “covered,” and graphia, which means “writing.” For thousands of years, people have used Steganography in various forms to protect the privacy of their conversations.
Steganography was initially used in ancient Greece in 440 BC when individuals wrote messages on wood and covered them with wax, which served as a covering medium.
Romans utilized a variety of invisible inks, and light or heat were used to read the messages they concealed.
Microdots were complete documents, images, and plans that had been shrunk down to the size of a dot and were introduced by the Germans during World War II and attached to regular paperwork.
Additionally, null ciphers were utilized to cloak plain text hidden messages with an innocent appearance.
Modern steganographic methods and tools are widely used to ensure that our data remains private. You might be wondering if Steganography and cryptography are the same thing. They are actually two distinct ideas and this Steganography tutorial outlines their key distinctions.
How Does Steganography differ from Cryptography
Protecting a message or piece of information from outsiders is the main objective of both. To protect the information, each uses a completely different method.
Through the use of cryptography, data is converted into cipher text that cannot be decoded without a special key. As a result, anyone who were to intercept this message and decrypt it could immediately see that some sort of encryption had been used. Steganography, on the other hand, hides the message while leaving the information’s format unaltered.
In other words, while sending private information, Steganography is more covert than cryptography. The drawback is that if a secret is found, it is simpler to extract the hidden message. The remaining portions of this Steganography tutorial will teach us about various Steganography methods and apparatus.
Steganography Techniques
Steganography can be categorized into five forms based on the characteristics of the cover item (the physical object in which secret data is hidden):
Text Steganography
Image Steganography
Video Steganography
Audio Steganography
Network Steganography
Text Steganography
Information is being concealed through text Steganography in the text files. To create understandable texts, it may be necessary to alter the format of already existing text, change the words inside a text, create random letter sequences, or use context-free grammars. There are many ways to conceal the data in the text, including:
Format Based Method
Random and Statistical Generation
Linguistic Method
Image Steganography
Picture Steganography is the practice of concealing data by using the cover item as the image. Images are frequently employed as a cover source in digital Steganography because they contain a large amount of bits in their digital form. There are many techniques for concealing information within an image. Typical methods include:
Least Significant Bit Insertion
Masking and Filtering
Redundant Pattern Encoding
Encrypt and Scatter
Coding and Cosine Transformation
Audio Steganography
In audio Steganography, the covert message is inserted into an audio signal, changing the binary order of the associated audio file. Comparatively speaking, image Steganography is significantly easier to use than digital sound Steganography for the purpose of concealing hidden messages. Various audio Steganography techniques include:
Least Significant Bit Encoding
Parity Encoding
Phase Coding
Spread Spectrum
This technique conceals the data in sound files such as WAV, AU, and even MP3.
Video Steganography
You can conceal various types of data in digital video formats using video Steganography. The benefit of this type is that a significant quantity of data can be concealed inside and that it is a moving stream of sounds and visuals. This can be compared to an amalgamation of audio and image Steganography. There are two primary categories of video Steganography:
Embedding information in raw, uncompressed video and later compressing it
Directly incorporating data into the compressed data stream
Network Steganography (Protocol Steganography)
It is a method of incorporating data into network control protocols used for data transfer, including TCP, UDP, ICMP, and others. In some hidden channels that you may locate in the OSI model, you can employ Steganography. For instance, you can obfuscate data in some optional or header fields of a TCP/IP packet.
Different software tools are available for Steganography in the modern, digital environment. The remaining sections of this tutorial on Steganography will examine some of the common steganographic tools and their features.
Best Tools to Perform Steganography
Steganography is a feature of a lot of software. A handful offer encryption before data concealment, while some only offer standard Steganography. These are the Steganography tools that can be used for free:
Free Steganography software called Stegosuite was created in Java. You may simply conceal sensitive information in image files with Stegosuite.
A secret file can be concealed in an image or audio file using the free and open source Steganography program Steghide.
A free program called Xiao Steganography can be used to conceal data in WAV or BMP files.
Another free portable tool to conceal text inside an image file is called SSuite Picsel, however it approaches the problem differently from other utilities.
With the help of OpenPuff, a reputable steganographic program, you can store data in picture, audio, video, or flash files.
Conclusion
In summary Steganography was created to facilitate safe communication. However, technology is being utilized for personal gain by criminals and terrorist groups alike. Therefore, both attack and defense can greatly benefit from knowing how to conceal data via Steganography and prevent such data from being utilized improperly.
Thank You For Reading!
Below is one of the newest videos on Steganography by David Bombal. In it, he speaks to Occupy the Web (OTW) who gives a tutorial on Windows and Linux about Steganography.