What Is Steganography In Data Security And Why It Is Important ?

We have already seen a brief overview of data security and also a brief introduction to Cryptography in our previous post .

Now the next basic security-related term that is worth mentioning is Steganography. It is basically the art as well as the science of hiding communication in such a way that nobody aware of its existence in the communication. So it is completely different than the Cryptography process. Let’s dive into the details now .

In the later section of this post, we further see the basic differences between the cryptography and steganography methods of security. So just relax and read further . 

What Is Steganography In The Field Of Security ?

Steganography is a technique of hiding the message, file and image within another message, file, or image. Steganography word is of Greek origin that means “covered writing” or “secret writing” . In other words, it is the art as well as the science of hiding the communication in such a way that know body aware the existence of communication.

The goal of hiding messages, files, and images is to fool attackers and not even allow attacker to detect that there is another message hidden in original message. The main aim of Steganography is to achieve high security and encode the sensitive data in any cover media like images, audio, video and send it over insecure channel such as
Internet.

Even if there is a small change in stenographic image or data will change complete meaning of the messages. In Steganography the term called as Steganalysis is similar to cryptanalysis in cryptography.

Like cryptanalysis , the goal of steganalysis is to identify suspected messages, files, and images, to determine whether any hidden or encoded information is available into those messages, and also to try and gain access to those messages, files, and images.

Attacks on steganographic techniques are very similar to attacks on cryptographic techniques/ algorithms and similar techniques apply. The strength of a steganographic algorithm depends on its ability to successfully
withstand attacks.

What Are The Attacks In Steganography ?

Following are some of the possible attacks in Steganography :

1. Stego-only attack

In this type of attack, only the medium (files and images) containing hidden data is available for analysis. This attack also called as Visual attack.

2. File only attack

The attacker has access the file he must determine if there is a message hidden information inside that file.

3. Known carrier attack

In this type of attack, the steganalyst has access to both the original image and the image containing the hidden information are available and compared to assume the message. The stego object (that contains the hidden information) is compared with the cover object and the differences are detected. This attack also called file an original copy.

It might happen that the attacker has a copy of both the file i.e. the encoded message and a copy of the original file.
If the two files are different, then the attack may guess that there must be some hidden information inside a file.
Such type attacks helps attacker to destroy the hidden information by simply replacing it with the original message.

4. Reformat Attack

Most popular attack on steganography is a reformated attack, in this attack attacker change the format of the file (BMP, GIF, JPEG) because different file formats don’t store data in the exactly same way.

5. Destroy Everything Attack

An attacker could simply destroy the message and all related information. This can works correctly because there are different file formats are used to store data in different ways.

6. Known message attack

In this type of attack, the original message prior to embedding and when transmitting over the Internet is known to sender.

7. Multiple Encoding of a Files

The attacker gets n different copies of the files with n different messages. It might happen if some companies are inserting different tracking information into each file. The attacker tracks all the data during the transmission then he may try to replace the tracking information with its own available information.

8. Compression Attack

One of the simplest attacks is to compress the file. This type of attack tries to remove the unrelated information from a file during compression then what is the use of hiding the data if extraneous information is removed.

What Is The Difference Between Steganography And Cryptography ?

Steganography is a technique of hiding the message, file, and image within another message, file or image .      Cryptography  is the science of secret writing of information/message and makes them nonreadable 

In Steganography, only the sender and the receiver know the existence of the message. In cryptography, the existence of the encrypted message is visible to the world . 

Techniques used to achieve steganography are Least Significant Bit (LSB), Spatial Domain, Still imagery steganography, Audio, and Video Steganography.

Techniques used to achieve cryptography are Substitution Techniques, Transposition Techniques, RSA, DES, and AES. (all this will be covered in the consecutive posts)

Hope you really liked this post , stay tuned for more interesting stuff in this series .