AU2021100948A4 - Enhancing cyber security using high speed hybrid authentication technique - Google Patents

Abstract

The present disclosure relates to an enhancing cyber security using high speed hybrid authentication technique. A novel high performance hybrid authentication technique using one dimensional chaotic logistic map in multi-core environment for enhanced cyber security is provided. Random numbers generated with chaotic functions have been validated with 15 randomness tests combined in NIST test suite. The acceptance or rejection of a sequence is based on a null hypothesis. The sequences pass majority of the tests for only certain seed and control parameters. The encryption of the secret information prior to its embedding in the cover has been achieved with a robust Recursive Prime non-prime Substitution technique. The statistical results indicate highly imperceptible stego images validated with histograms, PSNR and SSIM values. 22 w1 q c co o C 00 0 ~~0 E c - -E 9 r 0= Eu w C U 8 e a o "0.2 26 00 o o~ w: o o4a -v - C 0 co E cv cu j 0 0 ae a e c cv 4 c a O O0 i U 20 CL"0 .. Co0 o e r -0 cvWL OJ 4 - 02:- > ~Bajo wt ~ F 2 4 vh L C6 Clv C) 2oV o

Description

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ENHANCING CYBER SECURITY USING HIGH SPEED HYBRID AUTHENTICATION TECHNIQUE FIELD OF THE INVENTION

The invention relates to high performance hybrid authentication technique that utilizes both cryptography and least significant bit steganography in a multicore environment for enhancing cyber security.

BACKGROUND OF THE INVENTION

With the fast advancements in communication technologies, exchange of the digital media over the internet has increased tremendously. As a consequence, cyber security has emerged as the greatest challenge in recent times. Encryption techniques used to assure security in all type of transactions over internet lead to another challenge of time complexity in execution of these techniques.

High Performance Computing (HPC) provides a solution to this issue. HPC has the potential to improve security on both physical and digital fronts. HPC capabilities transform the security field, securing huge information, in least amount of time. The availability of multi-core processors facilitates high performance computing.

Steganography and cryptography techniques are widely used in multifaceted applications to achieve better security. Integrating cryptography and steganography together provide an additional layer of security to the confidential information to be sent through open internet. Our system performs steganography and cryptography at the same time and also deals with parallelization of cryptographic and chaotic LSB (CLSB) steganographic technique with shared memory OpenMP API, in order to reduce the execution time.

The combination of a strong encrypting scheme and steganographic technique is proposed to ensure safety of the confidential message during transmission. This method uses chaotic one dimensional logistic function and a Recursive Positional Substitution Based on Prime-Non Prime encryption Technique to first encrypt the secret message. Then, the scrambled confidential information is hidden in a suitable carrier which is securely transmitted to deliver the hidden information.

Crypto systems can be made more secure and robust by applying chaotic functions in information security. Varieties of random number generators are available and used for implementing cryptographic and steganography techniques. Recently, chaos based steganography techniques have become an interesting area of research due to the unique characteristics of chaos. Chaos theory deals with the behavior of nonlinear systems. Although some systems such as weather, politics, astronomy etc. appear to be unpredictable, chaotic mathematical functions are capable of explaining the underlying orderly pattern and predicting its behavior. These functions are extremely sensitive to initial conditions therefore a small fluctuation in the input causes large changes in the response. In addition to security, speed of the algorithm plays an important role in real time applications where we need faster encryption and decryption process. There are different approaches used for speedup like hardware approach, pipeline method and software approach of parallelization. Our invention involves software based approach of parallelization that utilizes data parallelism with OpenMP. OpenMP is a standard API for programming shared memory computers. Nowadays the typical desktop computer processors have four or more independent CPU cores, which are called as multi-core processors to execute instructions. Parallel programming language come into play to execute instructions concurrently for multi core architecture.

SUMMARY OF THE INVENTION

Invention relates to highly secure, robust and scalable chaos LSB based hybrid authentication technique. Three level security has been provided to the confidential information in the proposed technique which has been achieved through shared memory based parallel implementation of a hybrid technique.

In an embodiment, a method for enhancing cyber security using high speed hybrid authentication technique is disclosed. The method comprises:

reading secret image dividing into blocks of different sizes and converting the secret image into binary stream of data with finite number of blocks of finite length; applying RPSP encryption technique to the blocks of secret data, as per generating function for reorienting the positions of the bits of each of the blocks using a generating function; generating random sequences using chaotic logistic map function for different values of seed and control parameters; validating the random sequences by applying NIST test suite and recording seed and control parameters for which random sequence qualifies majority of tests; and applying LSB steganography by embedding encrypted secret data bits in LSB's of the cover data bytes. In an embodiment, generating function is aiming to orient the positions of different bits, is applied on a block s of size n to generate an intermediate block t of the same size.

In an embodiment, for a block of finite size (n), a finite number of iterations (I) are required to regenerate the source block, where for an iteration, the source is the target block of the previous block and for the 1st iteration, the source is the source block of the entire technique.

In an embodiment, in chaos based LSB steganography chaotic sequences are generated using a nonlinear, deterministic, chaotic function, wherein the sequences are used for embedding the encrypted image received by RPSP encryption into original cover image, wherein it is important to mention that the random sequences qualifying majority of the NIST tests have been applied prior to incorporating these in the LSB steganography.

In an embodiment, the images are converted into binary streams of data, wherein each byte of the cryptographic secret is modified by ex-oring with the binary random sequences obtained by ID Logistic map. In an embodiment, the LSB of the eight cover image bytes is replaced with modified secret byte, taking one bit for each cover byte, wherein it is worth specifying here that size of secret has to be within the limit of 1/8 times the size of the cover as the embedding process proceeds with hiding 1 bit of secret in 8 bits of cover image. In an embodiment, a process for encrypted secret data bits in LSB's comprising: reading the cover image and converting it into sequence of binary stream; reading crypto secret data and generating random sequence of 8 numbers using logistic function and compute average; comparing each element of array with average to obtain a new sequence by replacing MSB in all places of array; taking one byte of secret data and performing XOR operation on one byte of secret data and new sequence to obtain new secret data; replacing LSB of eight bytes of cover image with 8 bits of new secret image, wherein replacing of LSB is repeated for all bytes of cover image till the secret is completely embedded; and combining the cover bytes embedded with secret data and obtain stego image.

In an embodiment, the chaotic numbers generated with ID logistic map are averaged, converted into binary stream and ex-ored with stego image bytes. The secret bytes are obtained by extracting and combining LSBs from the ex-ored data bytes. In an embodiment, a process for extracting and combining LSBs comprises: reading the cover image and converting it into stream of binary digits; generating random sequence of 8 numbers using logistic function and computing average; comparing each element of array with average and thereby obtaining a new sequence by replicating MSB in all places array; reading one byte of crypto secret image and performing XOR operation of secret image and new sequence; combining LSB of the data bytes to from secret data.

In an embodiment, cryptographic secret obtained in the last step of extraction is required to be decrypted for getting the original secret, wherein RPSP decryption process works is similar manner as that of RPSP encryption however the number of iterations to retrieve the original data is different.

In an embodiment, random numbers generated with chaotic functions have been validated with 15 randomness tests combined in NIST test suite, wherein the acceptance or rejection of a sequence is based on a null hypothesis. The sequences pass majority of the tests for only certain seed and control parameters.

In an embodiment, secret image has been first converted into a cipher text with RPSP cryptography technique. Cipher text and the chaotic sequences are Xored to provide additional layer of security. This two folded secret data is then embedded in the cover image to form stego image to be sent for transmission through a channel. In RPSP based image encryption technique, the secret image is converted into binary stream of data, with finite number of blocks of finite length, then the positions of the bits of each of the blocks is re oriented using a generating a function.

With the proposed techniques, the original block is reproduced after a finite number of reiterations. Therefore, one of the intermediary blocks can be considered as an encrypted block for transmission. Decryption process is similar to the encryption. Original block of data can be retrieved by following the same process for a different number of times.

The data once encrypted using RPSP encryption technique is required to be embedded into the image using chaos based LSB steganography. In chaos LSB steganography chaotic sequences are generated using a nonlinear, deterministic, chaotic function. These sequences are used for embedding the encrypted image received by RPSP encryption into original cover image. It is important to mention that the random sequences qualifying majority of the NIST tests have been applied prior to incorporating the LSB steganography. Despite being characterized by unique and desirable properties of cryptography, the randomness of the generated sequence of pseudo random bits (PRB) from a chaotic map for different seed and control parameters is required to be tested. The National Institute of Standards & Technology (NIST) test suite for random numbers (the de facto standard) for validation of randomness has been used on sequences generated by the chaotic logistic map. The NIST test suite, like many statistical tests, is based on hypothesis testing. The null hypothesis is used to determine whether the generated sequence of ones and zeroes is random or not. A statistic known as p-value is calculated for 15 tests specified with the suite and is used to accept or reject a sequence. Randomness tests are used to analyze the distribution of numbers in the given range which can be done by various methods. Validation of the hybrid technique in terms of imperceptibility and quality of the encrypted images has been carried out with the following metrics: Mean Square Error (MSE), Peak Signal to Noise Ratio (PSNR) and Structural Similarity Index (SSIM). SSIM indicates structural similarity between the original and the encrypted image. The greater values of PSNR and less MSE indicate a small perceived error. SSIM closer to 1 means that perceived change in structural information is very less and 1 means the cover and stego images are identical.

The driving motivation behind the proposed parallel implementation is the potential reduction of the execution time of hybrid technique. Execution time of a parallel technique is essentially affected by a number of factors that include platform architecture, type of compiler , operating system, and parallel programming model. For programming of shared memory systems using single program multiple data (SPMD) model, OpenMP is the de facto standard. The OpenMP is an API for writing multithreaded applications that includes a set of compiler directives, environment variables and library routines for parallel application developers. The library routines and the environmental variables control the runtime system. Performance of parallel execution is calculated as observed by speedup ratio and efficiency. To further clarify advantages and features of the present disclosure, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF FIGURES

Figure 1: depicts the Flow chart of Hybrid Authentication Technique

Figure la: depicts the process of RPSP data shuffling with prime non-prime substitution

Figure 1b: is an example of LSB steganography process

Figure 2 : depicts the Parallel programming model for RPSP technique

Figure 3: depicts the Parallel programming model for LSB steganography

Figure 4(a), 4(b) & 4(c): depicts the Histogram analysis with images of different dimensions

Figure 5(a) ,5(b) & 5(c): shows the Encryption and Decryption Time scalability analysis with images of different dimensions

Figure 6(a), 6(b) & 6(c) : shows the Speed up analysis for data sets of different sizes of cover and secret images

Figures 7A and 7B illustrate histogram of the cover and stego images from the data set.

DETAILED DESCRIPTION

For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not intended to be restrictive thereof.

Reference throughout this specification to "an aspect", "another aspect" or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, appearances of the phrase "in an embodiment", "in another embodiment" and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or sub-systems or elements or structures or components proceeded by "comprises...a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.

Embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings.

Referring to Figure 1, a flow chart of a method for multicore implementation and performance analysis of hybrid authentication technique is illustrated in accordance with an embodiment of the present disclosure. At step 102, the method 100 includes reading secret image dividing into blocks of different sizes and converting the secret image into binary stream of data with finite number of blocks of finite length.

At step 104, the method 100 includes applying RPSP encryption technique to the blocks of secret data, as per generating function for reorienting the positions of the bits of each of the blocks using a generating function. At step 106, the method 100 includes generating random sequences using chaotic logistic map function for different values of seed and control parameters.

At step 108, the method 100 includes validating the random sequences by applying NIST test suite and recording seed and control parameters for which random sequence qualifies majority of tests. At step 110, the method 100 includes applying LSB steganography by embedding encrypted secret data bits in LSB's of the cover data bytes.

In an embodiment, generating function is aiming to orient the positions of different bits, is applied on a block s of size n to generate an intermediate block t of the same size. In an embodiment, for a block of finite size (n), a finite number of iterations (I) are required to regenerate the source block, where for an iteration, the source is the target block of the previous block and for the 1st iteration, the source is the source block of the entire technique.

In an embodiment, in chaos based LSB steganography chaotic sequences are generated using a nonlinear, deterministic, chaotic function, wherein the sequences are used for embedding the encrypted image received by RPSP encryption into original cover image, wherein it is important to mention that the random sequences qualifying majority of the NIST tests have been applied prior to incorporating these in the LSB steganography.

In an embodiment, the images are converted into binary streams of data, wherein each byte of the cryptographic secret is modified by ex-oring with the binary random sequences obtained by ID Logistic map.

In an embodiment, the LSB of the eight cover image bytes is replaced with modified secret byte, taking one bit for each cover byte, wherein it is worth specifying here that size of secret has to be within the limit of 1/8 times the size of the cover as the embedding process proceeds with hiding 1 bit of secret in 8 bits of cover image.

In an embodiment, a process for encrypted secret data bits in LSB's comprising:

reading the cover image and converting it into sequence of binary stream; reading crypto secret data and generating random sequence of 8 numbers using logistic function and compute average; comparing each element of array with average to obtain a new sequence by replacing MSB in all places of array; taking one byte of secret data and performing XOR operation on one byte of secret data and new sequence to obtain new secret data; replacing LSB of eight bytes of cover image with 8 bits of new secret image, wherein replacing of LSB is repeated for all bytes of cover image till the secret is completely embedded; and combining the cover bytes embedded with secret data and obtain stego image.

In an embodiment, the chaotic numbers generated with ID logistic map are averaged, converted into binary stream and ex-ored with stego image bytes. The secret bytes are obtained by extracting and combining LSBs from the ex-ored data bytes. In an embodiment, a process for extracting and combining LSBs comprises:

reading the cover image and converting it into stream of binary digits; Generating random sequence of 8 numbers using logistic function and computing average; Comparing each element of array with average and thereby obtaining a new sequence by replicating MSB in all places array; reading one byte of crypto secret image and performing XOR operation of secret image and new sequence; combining LSB of the data bytes to from secret data. In an embodiment, cryptographic secret obtained in the last step of extraction is required to be decrypted for getting the original secret, wherein RPSP decryption process works is similar manner as that of RPSP encryption however the number of iterations to retrieve the original data is different.

In an embodiment, random numbers generated with chaotic functions have been validated with 15 randomness tests combined in NIST test suite, wherein the acceptance or rejection of a sequence is based on a null hypothesis. The sequences pass majority of the tests for only certain seed and control parameters. Secret image has been first converted into a cipher text with RPSP cryptography technique. Cipher text and the chaotic sequences are xor-ed to provide additional layer of security. This two folded secret data is then embedded in the cover image to form stego image to be sent for transmission through a channel.

At step 102, the method 100 includes reading the secret image and converting it into binary stream of data, with finite number of blocks of finite length, then the positions of the bits of each of the blocks is re-oriented using a generating function g(s,t) at step 104. For a block s of size n the function shuffles the position of bits and generates a new intermediate block t of same size.

The generating function g(s, t), aiming to orient the positions of different bits, is applied on a block s of size n to generate an intermediate block t of the same size. The intermediate block t is generated by the following rules:

1. A bit in the position i (1 <= i <= n-2) in the block s becomes the bit in the position (n-i) in the block t, if (n-i) is a non-prime integer.

2. A bit in the position i (1 <= i <= (n-2)) in the block s becomes the bit in the position j (1 <= j <= (n-i-1)) in the block t, where j is the precedent prime integer (if any) of (n-i), if (n-i) is a prime integer.

3. A bit in the position n in the block s remains in the same position in the block t

4. A bit in the position (n-2) in the block s is transferred in the block t to the position unoccupied by any bit after rules 1, 2 and 3 are applied.

As an example, a source block is considered as- 01001011. After 1st iteration, the bit positions are shuffled according to the generating function and the obtained block of data is shown.

The shuffling procedure has been applied 5 times and the block of data obtained after 5th iteration is 01001011.

Source Block 0 1 0 0 1 0 1 1

1 2 3 4 5 6 7 8

Block After 1st Iteration 1 1 0 0 0 1 0 1

1 2 3 4 5 6 7 8

Block After 2nd Iteration 0 0 0 0 1 1 1 1

1 2 3 4 5 6 7 8

Block After 3rd Iteration 1 1 0 0 0 0 1 1

1 2 3 4 5 6 7 8

Block After 4th Iteration 1 0 0 0 1 1 0 1

1 2 3 4 5 6 7 8

Block After 5th Iteration (Source Block) 0 1 0 0 1 0 1 1

1 2 3 4 5 6 7 8

Now, for a block of finite size (n), a finite number of iterations (I)are required to regenerate the source block, where for an iteration, the source is the target block of the previous block and for the 1st iteration, the source is the source block of the entire technique.

It can be shown that if for the pth bit from MSB (1 <= p <= n) in the source block, ip is the number of iterations required to be re-oriented to its source position, the total number of iterations (I) required to regenerate the source block is LCM of il, i2, i3, ip.

The process of encryption is the sub set of the entire set of work to form the cycle for a given block. Any intermediate block during the process of forming the cycle may be considered as the encrypted block. Hence if the number of iterations required to form the cycle is I for a block of size n, the number of intermediate blocks generated in the cycle is (i-I), because each iteration generates one block and the final iteration generates the target block, which, in turn, is the source block. Therefore if the pth block formed in the cycle is considered to be the encrypted block, p may vary from 1 to (i-I).

In chaos based LSB steganography chaotic sequences are generated using a nonlinear, deterministic, chaotic function. These sequences are used for embedding the encrypted image received by RPSP encryption into original cover image. It is important to mention that the random sequences qualifying majority of the NIST tests have been applied prior to incorporating these in the LSB steganography.

The logistic map function used to produce non-periodic and non-convergent chaotic sequence is defined as

Yn+ = YYn(1 - Yn)

Where, initial seed yn and control parameter y can take values from the given intervals o y 4 and 0 yn : 1. The logistic map is chaotic when 3.5699456 yn 4, step 106 of method 100 generate random sequences using chaotic logistic map function for different values of seed and control parameters and step 108 validates the random sequence by applying NIST test suite and record the seed and control parameter for which random sequence qualifies majority of tests.

The embedding process begins with reading cover and the crypto secret image data obtained with RPSP technique described in Fig la. The images are converted into binary streams of data. Each byte of the cryptographic secret is modified by ex-oring with the binary random sequences obtained by ID Logistic map.

Step 110 of method 100 refers to the final embedding procedure which is described in detail in Fig.lb, illustration of LSB steganography process, LSB of the eight cover image bytes is replaced with modified secret byte, taking one bit for each cover byte. It is worth specifying here that size of secret has to be within the limit of 1/8 times the size of the cover as the embedding process proceeds with hiding 1bit of secret in 8 bits of cover image. This is the key point to achieve imperceptibility. The procedure is explained with steps as follows: 1. Read the cover image and convert it into sequence of binary stream. 2. Read the crypto secret data. 3. Generate random sequence of 8 numbers using logistic function and compute average. Let C represents the array of these numbers and A represents the average 4. For i from 1 to 8 5. Compare each element of array with average A. 6. if A>C[i] assign 1 to C[i] ,else 0. 7. Obtain a new sequence C, by replicating MSB(Most Significant Place)in all places of C. 8. Take one byte of secret data, say Si. 9. Perform XOR operation of Si and C 1 to obtain Si'. 10. Replace LSB of 8 bytes of cover image with 8 bits of Si'. 11. Repeat for all bytes of cover image till the secret is completely embedded. 12. Combine the cover bytes embedded with secret data and obtain stego image.

Extracting the secret information from the encoded image is similar to the embedding process as given in following algorithm. Chaotic numbers generated with ID logistic map are averaged, converted into binary stream and ex-ored with stego image bytes. The secret bytes are obtained by extracting and combining LSBs from the ex-ored data bytes. The procedure is explained with steps as follows:

1. Read the cover image and convert it into stream of binary digits. 2. Generate random sequence of 8 numbers using logistic function and compute average. Let C represents the array of these numbers and A represents the average. 3. For i from 1 to 8 4. Compare each element of array with average A. 5. if A>C[i] assign 1 to C[i], else 0. 6. Obtain a new sequence C 1 by replicating MSB in all places of C. 7. Read one byte of crypto secret image say Si'. 8. Perform XOR operation of Si' and C1 .

9. LSB of the data bytes obtained in step 8 are combined to from secret data Sl.

The cryptographic secret obtained in the last step of extraction is required to be decrypted for getting the original secret. RPSP decryption process works is similar manner as that of RPSP encryption however the number of iterations to retrieve the original data is different.

Iterations required to generate the source block of data is a key factor in deciding the iterations that can be performed to get the encrypted block. As an example, if the total number of iterations required to generate the source block is T, we can send an encrypted block on which the number of iterations performed is i where (1 i< (T - 1). In this case the number of iterations required to decrypt the encrypted block will be (T-i).

The security can be enhanced by encrypting the blocks with different sizes and with different number of iterations for each block.

Time elapsed for encryption and decryption of the data using the proposed technique can be reduced to a great extent by performing loop level parallelism. The proposed parallel models are based on distributing the data across different threads that operate on the data in parallel. A data parallel model contains a definite set of instructions to be performed on an array of elements.

Fig. 2 shows the parallel programming model for implementing RPSP technique on the secret data. Reading the image and dividing the image into blocks has been done with a master thread i.e. serial execution and the shuffling operations have been grouped in to a set of common tasks.

The blocks of data have been assigned to different threads for shuffling all blocks at the same time. As the threads defined in the compilation increase, the execution time gets decreased due to division of tasks among threads. After all blocks of data are processed, the results are combined and an encrypted secret is obtained. The combining of results from all threads is done again by the master thread.

Fig. 3 shows the parallel model for LSB steganography where the encrypted data obtained through the previous model. Reading of cover image, RPSP encrypted secret and the generation of chaotic sequences has been performed by master thread and again the steganography tasks are combined in a loop. Different blocks of cover and encrypted secret along with the chaotic sequence have been assigned to threads executing in parallel. The results obtained from individual threads have been combined to form the final stego image to be sent for transmission.

Identifying whether the algorithms to be parallelized is memory-bound or computing-bound is essential before applying OpenMP directives. A memory-bound algorithm contains a few computational operations in one memory access operation. Otherwise, algorithm is called compute-bound. The proposed encryption algorithm is compute-bound and does not require memory transfers and synchronization.

To ensure more effectiveness of RPSP technique, it is suggested to use different size blocks. Improvement in computational complexity with same and small size blocks has been found to be insignificant but different size blocks offer better security albeit enhancing computational complexity.

Concurrency in encryption algorithm allows to execute it in parallel. Blocks of secret data is divides the data into blocks and assigning blocks to threads. The resulting code is platform independent and the number of cores could be specified while executing the program. With blocks of different sizes, comparison of the execution times has been carried out while using different number of threads and presented.

Statistical validation of random numbers, statistical validation of the technique and performance analysis of the parallel programming model has been performed. Statistical validation of the chaotic numbers have been done with NIST tests suite. Statistical validation of the technique has been done with Histogram analysis, PSNR, MSE, SSIM and ED metrics. Finally the performance analysis of parallel implementation has been shown in terms of encryption decryption time, speed up and efficiency of parallelization.

NIST tests suite contains 15 statistical tests for validating the randomness of binary sequences. Tests result in p values which are then analysed for accepting or rejecting a sequence. P-values were obtained for sample sequences considering different combinations of seed and control parameters. Logistic map for many such combinations passes majority of the tests from NIST test suite. Result of one of the sets with p-values is given below.

The above shown are the p-values obtained by applying 15 tests from NIST test suite on a chaotic sequence. This test sequence was generated using logistic function for the initial value x=0.000001. and control parameter =3.999999. The sequence passes majority of the tests as indicated by 'True' values. Sequences which qualified majority tests were applied in the proposed steganography technique.

For statistical validation of the technique, histogram analysis , peak signal to noise ratio (PSNR) , Mean square error (MSE) , Structural similarity index (SSIM) and Euclidean distance (ED) were calculated. Data sets considered for statistical analysis are a set of standard images used commonly in image processing research.

The comparison has been made between original cover and the stego image obtained after embedding.

Histogram of the cover and stego images from the data set shown in table above has been plotted and shown in Fig.4 The technique result in highly imperceptible results as evidenced from the histograms.

Scalability analysis of the proposed parallel hybrid authentication technique has been presented for encryption/decryption of different sizes of cover and secret data. Performance of the parallel version of the hybrid authentication technique on three test samples in which size of the cover vary from 19 MB to a maximum of 3.4 GB are presented.

The multicore version of the hybrid authentication technique has been applied to data sets and executed on 16 core 2x E5-2680 v3 2.5 GHz/12-Core "Haswell" Intel Processor, 64 GB RAM HPC facility using Open MP directives.

Fig. 5 show the encryption and decryption time elapsed in execution of three data sets. The execution has been done by increasing threads from 1 to 20. The time elapsed in both encryption and decryption process is approximately the same. As the number of threads increase, a proportionate decrease in the execution time for both the operations have been observed.

Speed up ratio with respect to number of threads indicate the scalability of the parallel model. Fig. 6 show the speed up graphs obtained for the three data sets. Speed up ratio has been calculated for encryption times for the samples and perfectly scalable results have been observed up to 20 threads. Beyond this, a decline in the speed up ratio was observed.

The graphs are linear indicating the balanced load on threads assigned for execution of the parallel algorithm. Linear speed up has been observed when number of threads for execution is increased from 1 to 20. Significant improvement in time complexity for all test samples have been observed. Throughput obtained is directly proportional to the size of images.

Hybrid technique ensures confidentiality of the data. Statistical validation of the technique indicates high quality of the stego images. Histograms reveal very high imperceptibility. The parallel programming model has been tested for scalability. The execution results indicate highly scalable results specifically for large size images.

Figures 7A and 7B illustrate histogram of the cover and stego images from the data set.

Histogram of the cover and stego images from the data set shown in table above has been plotted and shown in Fig.4 The technique result in highly imperceptible results as evidenced from the histograms.

The method developed in accordance with the present disclosure are improved at developing of a method for enhancing cyber security using high speed hybrid authentication technique. The disclosure facilitates a novel high performance hybrid authentication technique using one dimensional chaotic logistic map in multi-core environment for enhanced cyber security. The disclosure facilitates random numbers generated with chaotic functions have been validated with 15 randomness tests combined in NIST test suite. The acceptance or rejection of a sequence is based on a null hypothesis. The sequences pass majority of the tests for only certain seed and control parameters. The disclosure facilitates encryption of the secret information prior to its embedding in the cover has been achieved with a robust Recursive Prime non-prime Substitution technique. The disclosure facilitates statistical results indicate highly imperceptible stego images validated with histograms, PSNR and SSIM values. The disclosure facilitates single process multiple data model for the hybrid authentication technique and its multi-core implementation with OpenMP directives. The disclosure facilitates average speed up of 8.3998,10.501 and 10.548 were obtained for cover images of sizes 19 MB, 1.9 GB and 3.4 GB respectively. Average efficiencies of 84.8661, 100.264 and 100.6197 have been obtained for cover image of sizes 19 MB, 1.9 GB and 3.4 GB respectively. The disclosure facilitates linear speed up for small and large size images have been observed. The scalability results indicate that the parallel version of the proposed parallel LSB steganography implemented on multi-core architecture using OpenMP is scalable up to a limit. The disclosure facilitates parallel implementation of the algorithm in OpenMP multicore environment, has been tested for 1 to 20 cores on Intel*Haswell Processor. The disclosure facilitates highly secure and maintaining high imperceptibility is also a contributing factor. The proposed technique is an efficient technique for image steganography and its OpenMP implementation effectively deal with data transmission in the digital universe.

The drawings and the forgoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, orders of processes described herein may be changed and are not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts necessarily need to be performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples. Numerous variations, whether explicitly given in the specification or not, such as differences in structure, dimension, and use of material, are possible. The scope of embodiments is at least as broad as given by the following claims.

Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any component(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature or component of any or all the claims.

Claims (11)

WE CLAIM

1. A method for enhancing cyber security using high speed hybrid authentication technique, the method comprises: reading secret image dividing into blocks of different sizes and converting the secret image into binary stream of data with finite number of blocks of finite length; applying RPSP encryption technique to the blocks of secret data, as per generating function for reorienting the positions of the bits of each of the blocks using a generating function; generating random sequences using chaotic logistic map function for different values of seed and control parameters; validating the random sequences by applying NIST test suite and recording seed and control parameters for which random sequence qualifies majority of tests; and applying LSB steganography by embedding encrypted secret data bits in LSB's of the cover data bytes.

2. The method as claimed in claim 1, wherein generating function is aiming to orient the positions of different bits, is applied on a block s of size n to generate an intermediate block t of the same size.

3. The method as claimed in claim 1, wherein for a block of finite size (n), a finite number of iterations (I) are required to regenerate the source block, where for an iteration, the source is the target block of the previous block and for the 1st iteration, the source is the source block of the entire technique.

4. The method as claimed in claim 1, wherein in chaos based LSB steganography chaotic sequences are generated using a nonlinear, deterministic, chaotic function, wherein the sequences are used for embedding the encrypted image received by RPSP encryption into original cover image, wherein it is important to mention that the random sequences qualifying majority of the NIST tests have been applied prior to incorporating these in the LSB steganography.

5. The method as claimed in claim 1, wherein the images are converted into binary streams of data, wherein each byte of the cryptographic secret is modified by ex oring with the binary random sequences obtained by ID Logistic map.

6. The method as claimed in claim 1, wherein the LSB of the eight cover image bytes is replaced with modified secret byte, taking one bit for each cover byte, wherein it is worth specifying here that size of secret has to be within the limit of 1/8 times the size of the cover as the embedding process proceeds with hiding 1 bit of secret in 8 bits of cover image.

7. The method as claimed in claim 1, wherein a process for encrypted secret data bits in LSB's comprising:

reading the cover image and converting it into sequence of binary stream; reading crypto secret data and generating random sequence of 8 numbers using logistic function and compute average; comparing each element of array with average to obtain a new sequence by replacing MSB in all places of array; taking one byte of secret data and performing XOR operation on one byte of secret data and new sequence to obtain new secret data; replacing LSB of eight bytes of cover image with 8 bits of new secret image, wherein replacing of LSB is repeated for all bytes of cover image till the secret is completely embedded; and combining the cover bytes embedded with secret data and obtain stego image.

8. The method as claimed in claim 1, wherein the chaotic numbers generated with ID logistic map are averaged, converted into binary stream and ex-ored with stego image bytes. The secret bytes are obtained by extracting and combining LSBs from the ex-ored data bytes.

9. The method as claimed in claim 8, wherein a process for extracting and combining LSBs comprises:

reading the cover image and converting it into stream of binary digits; generating random sequence of 8 numbers using logistic function and computing average; comparing each element of array with average and thereby obtaining a new sequence by replicating MSB in all places array; reading one byte of crypto secret image and performing XOR operation of secret image and new sequence; combining LSB of the data bytes to from secret data.

10. The method as claimed in claim 8, wherein cryptographic secret obtained in the last step of extraction is required to be decrypted for getting the original secret, wherein RPSP decryption process works is similar manner as that of RPSP encryption however the number of iterations to retrieve the original data is different.

11. The method as claimed in claim 8, wherein random numbers generated with chaotic functions have been validated with 15 randomness tests combined in NIST test suite, wherein the acceptance or rejection of a sequence is based on a null hypothesis. The sequences pass majority of the tests for only certain seed and control parameters.

Figure 1a: RPSP data shuffling with prime non-prime substitution

Figure 1b:Illustration of LSB steganography process

Figure 2 : Parallel programming model for RPSP technique

Start

Cover Image is di- Secret Image is di- n Chaotic sequences are generated vided into n blocks vided into n blocks with different control parameters

Parallel Implementation

Thread 1 Thread 2 Thread n 8 bits of Cover Im- 8 bits of Cover Im- 8 bits of Cover Im- age from first age from second age from last block

MSB of the 8 bit MSB of the 8 bit MSB of the 8 bit chaotic sequence chaotic sequence chaotic sequence Embed- Embed- …….. Embed- ding Ex-Or ding Ex-Or ding Ex-Or

1 bit of secret 1 bit of secret 1 bit of secret Image from first Image from sec- Image from last block ond block block

Encoded Block Encoded Block Encoded Block

Figure 3: Parallel programming model for LSB steganography

(a)

(b)

(c)

Figure 4: Histogram analysis (a) Lena(512x512) , Lena(128x128 ) (b) Baboon(512x512) , Baboon(128x128) (c)Peppers(512x512), peppers(128x128 )

(b) (a)

(c) Figure.5:Encryption and Decryption Time scalability analysis of (a) cover: potw1802a.tif (19 MB) secret : potw 1810a.jpg (1.5 MB) (b) cover: eso1612a.tif (1.9 GB) secret : eso1119a.jpg 135 MB (c) cover: eso1705a.tif (3.4 GB) secret : eso1613a.jpg (314.7 MB)

(a) (b)

(c) Fig. 6: Speed up analysis for data sets (a) cover: potw1802a.tif (19 MB) secret : potw 1810a.jpg (1.5 MB) (b) cover: eso1612a.tif (1.9 GB) secret : eso1119a.jpg 135 MB (c) cover: eso1705a.tif (3.4 GB) secret : eso1613a.jpg (314.7 MB)