Blindspot: Indistinguishable Anonymous Communications

Communication anonymity is a key requirement for individuals under targeted surveillance. Practical anonymous communications also require indistinguishability - an adversary should be unable to distinguish between anonymised and non-anonymised traffic for a given user. We propose Blindspot, a design for high-latency anonymous communications that offers indistinguishability and unobservability under a (qualified) global active adversary. Blindspot creates anonymous routes between sender-receiver pairs by subliminally encoding messages within the pre-existing communication behaviour of users within a social network. Specifically, the organic image sharing behaviour of users. Thus channel bandwidth depends on the intensity of image sharing behaviour of users along a route. A major challenge we successfully overcome is that routing must be accomplished in the face of significant restrictions - channel bandwidth is stochastic. We show that conventional social network routing strategies do not work. To solve this problem, we propose a novel routing algorithm. We evaluate Blindspot using a real-world dataset. We find that it delivers reasonable results for applications requiring low-volume unobservable communication.Comment: 13 Page

Security System for Safe Transmission of Medical Images

This paper develops an optimised embedding of payload in medical images by using genetic optimisation. The goal is to preserve the region of interest from being distorted because of the watermark. By using this system there is no need to manually define the region of interest by experts as the system will apply the genetic optimisation to select the parts of image that can carry the watermark guaranteeing less distortion. The experimental results assure that genetic based optimisation is useful for performing steganography with less mean square error percentage

Application of Stochastic Diffusion for Hiding High Fidelity Encrypted Images

Cryptography coupled with information hiding has received increased attention in recent years and has become a major research theme because of the importance of protecting encrypted information in any Electronic Data Interchange system in a way that is both discrete and covert. One of the essential limitations in any cryptography system is that the encrypted data provides an indication on its importance which arouses suspicion and makes it vulnerable to attack. Information hiding of Steganography provides a potential solution to this issue by making the data imperceptible, the security of the hidden information being a threat only if its existence is detected through Steganalysis. This paper focuses on a study methods for hiding encrypted information, specifically, methods that encrypt data before embedding in host data where the ‘data’ is in the form of a full colour digital image. Such methods provide a greater level of data security especially when the information is to be submitted over the Internet, for example, since a potential attacker needs to first detect, then extract and then decrypt the embedded data in order to recover the original information. After providing an extensive survey of the current methods available, we present a new method of encrypting and then hiding full colour images in three full colour host images with out loss of fidelity following data extraction and decryption. The application of this technique, which is based on a technique called ‘Stochastic Diffusion’ are wide ranging and include covert image information interchange, digital image authentication, video authentication, copyright protection and digital rights management of image data in general

Improved method for image security based on chaotic-shuffle and chaotic-diffusion algorithms

In this paper, we propose to enhance the security performance of the color image encryption algorithm which depends on multi-chaotic systems. The current cryptosystem utilized a pixel-chaotic-shuffle system to encode images, in which the time of shuffling is autonomous to the plain-image. Thus, it neglects to the picked plaintext and known-plaintext attacks. Also, the statistical features of the cryptosystem are not up to the standard. Along these lines, the security changes are encircled to make the above attacks infeasible and upgrade the statistical features also. It is accomplished by altering the pixel-chaotic-shuffle component and including another pixel-chaotic-diffusion system to it. The keys for diffusion of pixels are extracted from the same chaotic arrangements created in the past stage. The renovation investigations and studies are performed to exhibit that the refreshed version of cryptosystem has better statistical features and invulnerable to the picked plaintext and known plaintext attacks than the current algorithm

Survey on Reversible Data Hiding in Encrypted Images Using POB Histogram Method

This paper describes a survey on reversible data hiding in encrypted images. Data hiding is a process to embed useful data into cover media. Data invisibility is its major requirement. Data hiding can be done in audio, video, image, text, and picture. Here use an image for data hiding especially digital images and existing method (Histogram Block Shift Base Method) HBSBM or POB. Now a day's reversible data hiding in encrypted images is in use due to its excellent property which is original cover image can be recovered with no loss after extraction of the embedded data. Also, it protects the original data. According to the level and kind of application one or more data hiding methods is used. Data hiding can be done in audio, video, text, and image and other forms of information. Some data hiding techniques emphasize on digital image security, some on the robustness of digital image hiding process while other's main focus is on imperceptibility of a digital image. The capacity of digital information which has to hide is also the main concern in some of the applications. The objective of some of the papers mentioned below is to achieve two or more than two parameters i.e. Security, robustness, imperceptibility and capacity but some of the parameters are trade-off which means only one can be achieved on the cost of other. So the data hiding techniques aiming to achieve maximum requirements i.e. security, robustness, capacity, imperceptibility etc. and which can be utilized in the larger domain of applications is desired. Related work for techniques used for data hiding in a digital image is described in this paper

Towards Blind Watermarking: Combining Invertible and Non-invertible Mechanisms

Blind watermarking provides powerful evidence for copyright protection, image authentication, and tampering identification. However, it remains a challenge to design a watermarking model with high imperceptibility and robustness against strong noise attacks. To resolve this issue, we present a framework Combining the Invertible and Non-invertible (CIN) mechanisms. The CIN is composed of the invertible part to achieve high imperceptibility and the non-invertible part to strengthen the robustness against strong noise attacks. For the invertible part, we develop a diffusion and extraction module (DEM) and a fusion and split module (FSM) to embed and extract watermarks symmetrically in an invertible way. For the non-invertible part, we introduce a non-invertible attention-based module (NIAM) and the noise-specific selection module (NSM) to solve the asymmetric extraction under a strong noise attack. Extensive experiments demonstrate that our framework outperforms the current state-of-the-art methods of imperceptibility and robustness significantly. Our framework can achieve an average of 99.99% accuracy and 67.66 dB PSNR under noise-free conditions, while 96.64% and 39.28 dB combined strong noise attacks. The code will be available in https://github.com/rmpku/CIN.Comment: 9 pages, 9 figures, 5 table

Security during Transmission of Data Using Web Steganography

The project entitled Steganography is to give security to a content record. Since the security of the data over the internet has raised a concern to the people. There are many methods to protect the data from going into the access of unauthorized people. Steganography can be used along with the encryption technique to secure the data. Steganography is used to hide the data or a secret message whereas cryptography is used to encrypt the message and make it difficult the people to read. So, the proposed system is to combine both steganography and cryptography for the secret data transmission. The transmission can be done by using an image as a carrier of data. This paper uses high-performance BMP steganography along with a substitution encryption methodology. The approach that is used here is IDEA (International Data Encryption Algorithm) algorithm which is used for encryption. The IDEA algorithm works as follows, it will take the TEXT document and mystery key as the input and gives the encrypted and BMP picture as the output for the sender side. There can additionally be “Voice Recognition System” framework so that it can use voice to decrypt the message. This is the future expansion or scope of this paper

Steganalysis in computer forenics

Steganography deals with secrecy and convert communication and today the techniques for countering this in the context of computer forensics has somewhat fallen behind. This paper will discuss on how steganography is used for information hiding and its implications on computer forensics. While this paper is not about recovering hidden information, tools that are used for both steganography and steganalysis is evaluated and identifies the shortcomings that the forensic analysts would face. In doing so this paper urges on what the stakeholders in the field of computer forensics needs to do to keep ahead of criminals who are using such techniques to their advantage and obscure their criminal activities