Dynamic hashing technique for bandwidth reduction in image transmission

Hash functions are widely used in secure communication systems by generating the message digests for detection of unauthorized changes in the files. Encrypted hashed message or digital signature is used in many applications like authentication to ensure data integrity. It is almost impossible to ensure authentic messages when sending over large bandwidth in highly accessible network especially on insecure channels. Two issues that required to be addressed are the large size of hashed message and high bandwidth. A collaborative approach between encoded hash message and steganography provides a highly secure hidden data. The aim of the research is to propose a new method for producing a dynamic and smaller encoded hash message with reduced bandwidth. The encoded hash message is embedded into an image as a stego-image to avoid additional file and consequently the bandwidth is reduced. The receiver extracts the encoded hash and dynamic hashed message from the received file at the same time. If decoding encrypted hash by public key and hashed message from the original file matches the received file, it is considered as authentic. In enhancing the robustness of the hashed message, we compressed or encoded it or performed both operations before embedding the hashed data into the image. The proposed algorithm had achieved the lowest dynamic size (1 KB) with no fix length of the original file compared to MD5, SHA-1 and SHA-2 hash algorithms. The robustness of hashed message was tested against the substitution, replacement and collision attacks to check whether or not there is any detection of the same message in the output. The results show that the probability of the existence of the same hashed message in the output is closed to 0% compared to the MD5 and SHA algorithms. Amongst the benefits of this proposed algorithm is computational efficiency, and for messages with the sizes less than 1600 bytes, the hashed file reduced the original file up to 8.51%

A new dynamic hash algorithm in digital signature

This paper presents adoption of a new hash algorithm in digital signature. Digital signature presents a technique to endorse the content of the message. This message has not been altered throughout the communication process. Due to this, it increased the receiver confidence that the message was unchanged. If the message is digitally signed, any changes in the message will invalidate the signature. The comparison of digital signature between Rivest, Shamir and Adleman (RSA) algorithms are summarized. The finding reveals that previous algorithms used large file sizes. Finally the new encoding and decoding dynamic hash algorithm is proposed in a digital signature. The proposed algorithm had reduced significantly the file sizes (8 bytes) during the transferring message

Secure digital signature schemes based on hash functions

This paper provides a literature review and analysis of the security systems and the emphasis is on digital signature, hashed message algorithm. The proposed algorithm introduces a novel technique for producing small-sized output of digital signature as a result; the new scheme is potentially practical: signing and verifying signatures are reasonably fast, and both speed and time are improved

DEVELOPMENT AND IMPLEMENTATION OF HASH FUNCTION FOR GENERATING HASHED MESSAGE

Steganography is a method of sending confidential information in a way that the existence of the channel in this communication remains secret. A collaborative approach between steganography and digital signature provides a high secure hidden data. Unfortunately, there are wide varieties of attacks that affect the quality of image steganography. Two issues that required to be addressed are large size of the ciphered data in digital signature and high bandwidth. The aim of the research is to propose a new method for producing a dynamic hashed message algorithm in digital signature and then embedded into image for enhancing robustness of image steganography with reduced bandwidth. A digital signature with smaller hash size than other hash algorithms was developed for authentication purposes. A hash function is used in the digital signature generation. The encoder function encoded the hashed message to generate the digital signature and then embedded into an image as a stego-image. In enhancing the robustness of the digital signature, we compressed or encoded it or performed both operations before embedding the data into the image. This encryption algorithm is also computationally efficient whereby for messages with the sizes less than 1600 bytes, the hashed file reduced the original file up to 8.51%

RELIABILITY EVALUATION OF RENEWABLE ENERGY-BASED POWER SYSTEM CONTAINING ENERGY STORAGE

In recent years, renewable energy based power plants, especially wind and solar farms are increasingly installed and operated for electric power generation. Uncertainty nature associated to the generated power of these power plants, arisen from variability of wind speed or solar radiation, effects on different aspects of power system such as reliability, operation, dynamic and so on. Energy storages in connection with renewable power plants can reduce the variability and uncertainty nature of these renewable resources. In recent years the flow batteries such as vanadium redox (VR) with large capacities are developed and so in this paper effects of these large-capacity energy storages on the reliability performance of power system containing large-scale wind and photovoltaic (PV) farms are investigated. The renewable energy-based power plants and also energy storages are different from conventional units, so, for study of power system containing these resources new methods and techniques must be developed. To this end in this paper for reliability evaluation of renewable-energy based power system containing energy storage, an analytical approach is proposed. This approach can be employed both in planning and also operation studies of the power system when large scale wind and photovoltaic farms with energy storages exist. Data associated to wind speed of Manjil and solar radiation of Jask regions both in Iran are utilized for studying the reliability evaluation of RBTS and also IEEERTS in planning phase

New implementation of hashing and encoding in digital signature

The purpose of introducing of this algorithm is a new method for designing a simple mechanism for producing a digital signature. Some applications like multi agent systems transfer messages with low size and capacity. The new algorithm minimizes the size of original file and gives us a dynamic and smaller size output. In this algorithm read the input file then hash the message and encode it. Finally modify the established code into a unique ID at Base 16. We concentrate on designing and implementation of functions of algorithm

Enhancing secured data hiding using dynamic digital signature for authentication purpose

As a significant verification method, digital signature algorithm introduces a technique to endorse what the contents of the message. This message has not been altered throughout the communication process. Due to this, it increases the receiver confidence that the message was unchanged. However, two issues that required to be addressed are large size of the ciphered data in digital signature and making it closer to the original file. The objective of this paper is to present the adoption of digital signature as a stegano-image into the main image and the LSB steganographic method is capable to increase the security. The benefits of this encryption algorithm are computational efficiency, digital signature with the size as small as 8 bytes and minimize bandwidth in comparison with other digital signature methods. In messages with the sizes smaller than 1600 bytes, the hashed file reduces the original file up to 8.51%