1.1 Introduction
Steganography is defined as the system of hiding secret or a confidential data in a cover media like image, text, video, and audio, in such a way that none other than the intended recipient knows the presence of data. In contrast to Cryptography, where the enemy is allowed to detect, intercept and modify messages without being able to violate certain security premises guaranteed by a cryptosystem, the goal of Steganography is to hide messages inside other harmless messages in a way that does not allow any enemy to even detect that there is a second message present". In this digital world, both the concepts i.e. The cryptography and steganography hide the data from the unintended recipients or an intruder. Due to this fact, the authors prefer a multilayer security by using the benefits of steganography. Steganography is the art and science of invisible or hidden communication.
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
In today’s society the most practical implementation of steganography is used in the world of computers. Data is the heart of computer communication and over the years a lot of methods have been created to accomplish the goal of using steganography to hide data. The trick is to embed the hidden object into a significantly larger object so the change is undetectable by the human ear. Steganography (hiding the existence of a message so as to keep it confidential) was also first developed in ancient times. An early example, from Herodotus (- a Greek historian), concealed a message – a tattoo on a slave’s shaved head – under the regrown hair. In modern terms, Steganography is usually implemented computationally, where cover works such as text files, images, audio files, and video files are altered in such a way that a secret message can be embedded within them. Although Steganography techniques are very similar to that of digital watermarking, one big distinction must be highlighted between the two. In digital watermarking, the focus is on ensuring that nobody can remove or alter the content of the watermarked data, even though it might be plainly obvious that it exists. Steganography on the other hand, focuses on making it extremely difficult to tell that a secret message exists at all. If an unauthorized third party is able to say with high confidence that a file contains a secret message, then steganography has failed.
Steganography is the art and science of invisible or hidden communication. Steganography is a method of hiding sensitive or confidential information or messages in carrier files in a way that no one apart from the sender and intended receiver no one even realizes that there is a hidden message inside the message cover (Conway M. 2003). They have being several research contribution to the work of steganography with different approaches of hiding information or messages in carrier file and transmitting the carrier file as stego image to the intended recipient at a destination without human perception.
The steganography concept can be implemented through various formats available worldwide. Various formats preferred are .jpeg, .gif, .png, .mp3, .mp4, .doc, .docx .bmp. Due to ease of availability of these formats on the internet, they are preferred to hide the secret message. Steganography research has been driven because of weakness in the cryptography systems that result in the security breach. Many tools and technologies created takes advantage of steganography techniques like coding in image, null ciphers, videos, audio, etc. (Cachin, 1998).
Steganography is a method of hiding sensitive or confidential information or messages in carrier files in a way that no one apart from the sender and intended receiver no one even realizes that there is a hidden message inside the message cover (Conway M. 2003).
The goal of steganography is to avoid drawing suspicion to the existence of a hidden message. This approach of information hiding technique has recently become important in a number of application areas. Digital audio, video, and pictures are increasingly furnished with distinguishing but imperceptible marks, which may contain a hidden copyright notice or serial number or even help to prevent unauthorized copying directly (Chen and Wu, 2009).
Military communications system makes increasing use of traffic security technique which, rather than merely concealing the content of a message using encryption, seek to conceal its sender, its receiver or its very existence. Similar techniques are used in some mobile phone systems and schemes proposed for digital elections. Some of the techniques used in steganography are domain tools or simple system such as least significant bit (LSB) insertion and noise manipulation and transform domain that involve manipulation algorithms and image transformation such as discrete cosine transformation and wavelet transformation. However, there are techniques that share the characteristic of both of the image and domain tools such as patchwork, pattern block encoding, spread spectrum methods and masking.
1.3 Statement of Problem
Investigation reveals the challenges of the existing system which includes the problem of security. The password method used in almost all commercial operating systems is probably not very strong against a sophisticated or unsophisticated attacker. The choice of data encryption comes next in the minds of those that want reduction of unauthorized access on confidential files or data. Security provided by the computer operating systems come with a preset super user account and password.
As stated earlier, visible encrypted messages will draw suspicion from others. This will make them attempt to decrypt the cipher text. Indirectly it raises the chance of message being viewed by third party in the exception of sender and viewer. However, by hiding or embedding the text file into image, it is hard to raise the suspicion of others whether it contains any secret message or not as the processed image had not look different from the original image in naked eyes. This will make the message more secure. Indirectly, only the sender and receiver know the treat behind the image and hence ensure that the message can only be viewed by the sender and receiver.
1.4 Aim and Objectives of the Study
The aim of the study is to Secure File Transmission System Using Steganographic Algorithm Data with the aid of JPEG Data Embedment techniques. In achieving this aim, the following specific objectives were laid out as follows to design and implement an application software that will:
- Store a text file (.txt) in image.
- Protect the text file (.txt) from being viewed by third party using encryption.
- Restore the stored text file in image.
- Encode a message in an image in a way that avoids drawing suspicion to the transmission of the hidden message.
- Ensure the data confidentiality and integrity along with the safe transmission of data over the web.
1.5 Significance of Study
Steganographic systems embed hidden messages inside the least significant bit layers of color natural images. The presence of these messages can be difficult to detect by using statistical steganalysis. Steganography is not just embedding the secret message into the digital image but also the intended receiver should also know the technique and method used to retrieve the message successfully. The receiver should be able to retrieve the message without drawing any attention from an unauthorized person or without anyone realizing that a secret communication is going on.
This study will be of immense benefit to other researchers who intend to know more on this study and can also be used by non-researchers to build more on their research work. This study contributes to knowledge and could serve as a guide for other study.
1.6 Scope of Study
The study focuses on the Secure File Transmission System Using Steganographic Algorithm Data with the aid of JPEG Data Embedment techniques. The proposed system combines cryptography and steganography to solve the problem of unauthorized data access of the existing system.
1.7 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Research material: availability of research material is a major setback to the scope of the study.
- Frequent power failure: This made the researcher append more money on fuel to ensure sustainable power.
- Financial Constraint: Insufficient fund tends to impede the efficiency of the researcher in sourcing for the relevant materials, literature or information and in the process of data collection (internet).
1.8 Definition of Terms
Encryption: A process of converting data/information into another form.
Decryption: A process of converting data/information (multimedia) back to its Original form.
Clear-text/plaintext: Original data/information before it is enciphered / scrambled.
Ciphered text/cryptogram: Information (multimedia) that has been converted into other symbols or form.
Ciphers: The secret code used to convert plain text message.
Hackers: People who steal information without permission.
Cryptography: This is process of hiding writing information.
Cryptographers: Those that hide writing information.
Cryptologist: Scientist who study different ways to protect information or data.
Cryptanalysis: Is the art of breaking of ciphers, some from program codes.
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