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In this paper Caesar and Vigenere methods have been used for table ciphering. Each record has unique and independent keys to the next record to get high security. The cipher text stored in script file that separates the content of fields by semicolon. The second part is the process of creating a new database using the Object called Data Access Object (DAO) and then create table and it is fields. The program gets plaintext of the table by applying the decryption rules of two methods.

The susceptibility of conventional Caesar cipher as a tool for encryption is a known fact not only due to its simplicity but also its practical infeasibilities. The requirement in today's complex age is of a method which has higher effectiveness in terms of being immune to cryptanalysis and at the same time is simple to implement. This paper is about a distinctive methodology by incorporation of a scheme that combines the use of dynamically generated keysets from grayscale images and a modified cipher. The unique aspect proposed yields higher security as each keyset derives its key values from the respective grayscale image which are used iteratively in the modified algorithm. Every iteration in the algorithm makes use of a different key value from the keyset, producing a new cipher-text in each iteration. Cipher-text produced in every iteration is encrypted in the succeeding iteration. This process repeats until all key values are used to obtain a highly-encrypted form of cipher-text. Hence, this sequential and iterative approach is proposed as an effective solution for present-day requirements of information security.

Cloud computing declared among the fastest growing technology. The amount of users using this technology has exploded. Therefore, cloud users expect their data to be safe on the cloud. We can secure the data from being accessed illegally by encrypting it with a key with various methods likewise Advanced and Data encryption standard. However, the issue with these encryption methods is that they are very complex and have a lengthy computing time due to finite key space. To overcome these problems, Cloud Service Providers (CSP) which is becoming a great area to have researched for ensuring the security of data with minimum processing time. This research paper emphasizes various secured encryption techniques which have efficient computing time. This paper focus on the complexity, efficiency, and the security of the algorithm used.

Cryptography and steganography are the two basic techniques which provide security and integrity of data. Numerous algorithms and ciphers have been developed contributing to the security of data. Even though these algorithms have contributed to data security, these are still vulnerable to attacks. The study was conducted to develop a multiphase and multiple encryption algorithm which will provide better security and safety of data. An android application is designed to implement and test the same to check its vulnerability. The algorithm will provide data encryption multiple times with each step being encrypted with a different algorithm along with randomization. Few strong and secure cryptography algorithms categorized into symmetric and asymmetric are incorporated in to the proposed work. The algorithms are referred to as Advanced Encryption Algorithm (AES-256 bits), RSA, Data Encryption Standard (DES), Blowfish, Caesar Cipher and ROT13. The validation of the proposed work is accomplished by comparing its results with the contemporary available algorithms based on the evaluation parameters such as time complexity, security and data size.

The issue of security of information is paramount in our society. There are many hackers around us to steal our private information such as passwords. To secure such information, we intend to create ciphertext. Ciphertexts are the words that can only be obtained by authorized persons or users. Ciphertexts can be obtained by performing encryption on the plaintexts. Ciphertexts do not have any meaning. These texts can only be understood after decryption. Our work shows that the information can be retrieved by the authorized person in a few milliseconds whereas it takes much time for an unauthorized person or a third party. In order to perform encryption, we have proposed an algorithm in such a way that it combines many algorithms such as the Caesar cipher, mono-alphabetic cipher, hill algorithms. Different algorithms are applied to individual cases like a plain text that is in uppercase, lowercase, special characters, and numbers. For each case, we have used different algorithms with different keys. We hope that we can suggest an approach for protecting the private information at a higher level.

Security of data or documents is a very important thing. Given that nowadays many exchange data electronically. It will result in a lot of processes that can compromise the security of data. Therefore, we need a way to be able to secure the important data that are not easily obtained by others who are not interested. One of the main that we can secure is the data in the form of text. The knowledge that can keep a message or data Cryptography is the science. In the event that the merger will be carried out or a combination of WAKE and Caesar Cipher methods. Mechanisms to improve security is to use encryption technology. Encryption is the conversion of an original text or plain text into the hidden text (cipher text) that usually berbetuk codes. And vice versa if the data is hidden the wish to be returned must decrypt it first. The step is to encrypt text data with the method and the result is encrypted WAKE back to Caesar Cipher method, so that the data to be kept secret remains safe.

Cryptography is one amongst the foremost fields of study lately because it is critical to keep up the confidentiality of the info that is distributed over the network. There are a unit numerous cipher techniques out there for encrypting the messages like vern am cipher, mono-alphabetic cipher, poly-alphabetic cipher, etc. one amongst the foremost fashionable cipher techniques is that the vigenere cipher. It's a poly-alphabetic cipher technique that uses the vigenere table for the method of coding of alphabets. This paper extends the vigenere table with numerical knowledge, so the numbers may be encrypted exploitation this system. It combines the coding method of Vigenere and Modified Caesar Cipher for obtaining the cipher text from the given plaintext and key.

Cryptography is about constructing and analyzing protocol that prevents third parties or the publi c from reading private messages. There are two techniques for converting data into no readable form:1) Transposition technique 2) Substitution technique. Caesar cipher is an example of substitution method. Caesar cipher has various limitations. In this pa per we have focused on the well known Caesar cipher techniques. Here in this paper our aim was to induce some strength to the Caesar cipher encryption technique. This proposed technique blended classical encryption with the some more techniques and This me thod is better in terms of providing more security for any given text message. In our experiments we took Caesar Ciphers as reference of Classical Techniques. To make it more secure we have used some techniques like we have divided the given plain text in five word group each. With the given key rearrange the group of letters without giving the space https://www.ijiert.org/paper-details?paper_id=141194

The Symmetric and Asymmetric Cryptographic techniques and algorithms as existing in the literature are either too simple and traditional or too complex to code and understand. In the current research work, a new Cryptographic technique is being proposed which is a blend of both. To show the effectiveness of the proposed "Cyclic Cryptographic Technique", it has been compared with well-known Cryptographic technique(s) such as Caesar Cipher, Vigenere Cipher and Affine Cipher and the result exceed the expectations.

Security of information has become a popular subject during the last decades, it is the balanced protection of the Confidentiality, Integrity and Availability of data, also known as the CIA Triad. In this work, we introduce a new hybrid system based on two different encryption techniques: two square cipher and Caesar cipher with multiples keys. This homogeneity between the two systems allows us to provide the good properties of the two square cipher method and the simplicity of the Caesar cipher method. The security analysis shows that the system is secure enough to resist brute-force attack, and statistical attack. Therefore, this robustness is proven and justified.

Caesar cipher is an ancient, elementary method of encrypting plain text message to protect it from adversaries. However, with the advent of powerful computers there is a need for increasing the complexity of such algorithms. In this paper, we contribute in the area of classical cryptography by providing a modified approach and expanded version for Caesar cipher using knowledge of mathematics and computer science. To increase the strength of this classical encryption technique we use the concepts of affine ciphers, transposition ciphers and randomized substitution techniques to create a cipher text which is nearly impossible to decode. We also increase the domain of characters which Caesar cipher Algorithm can encrypt by including all ASCII and extended ASCII characters in addition to alphabets. A complex key generation technique which generates two keys from a single key is used to provide enhanced security. We aim to propose a modified version of Caesar cipher substitution technique which can overcome all the limitations faced by classical Caesar Cipher., 6 pages, 7 figures

In this paper, a new technique for protected and locked broadcasting of message is presented. This approach uses improved version of ciphering with the combination of double phase encryption. To ripen this method of encryption, a simple technique of vertically selecting the text for ciphering is used. A 6 x 6 matrix based on the alphabets used in the text message. If the message is lengthy, the matrix can duplicate itself accordingly. Message will be fit in the matrix and remaining cells of the matrix will be filled by alphabets. After getting vertically scrambled text, substitution techniques for ciphering is used further to ensure secured transfer of message. The receiver will get to know about the length of the text and shift key for decryption procedure. By using this double phase encryption, the transmission of message will become more secure and robust. The main target of the technique proposed in this paper is that the information cannot be customized by any outsider or intruder.

Message is a privacy statement which is made by a person and addressed to another person with the consent of people who have made the message. But with the development of modern technology resulted in a high level of privacy for their safety message. Especially lately act haeker (security breaker) are increasingly rampant and alarming message makers. To address this, the authors will examine and discuss the cryptographic cipher to convey a secret message privacy. Message in the form of a password using cryptography in this paper Combining of Hill Cipher Method and Caesar Cipher Methods.In the operation process of encryption and decryption passwords cryptography, the steps using the Caesar CipherMethods, whereas in steps using keys by using Hill Cipher method. In the making and the first decoding the message makers and recipients know how the operation technique. Thus the expected delivery of message privacy secured.

Playfair cipher is the form of block cipher which has no limit on the number of characters in a message it can do, but it operates on block of characters encrypting and decrypting two characters at a time cipher. In this, the plain text digrams are converted to cipher text digrams and vice versa using a pre-shared key. This is achieved by performing several operations column wise row wise and by creating rectangular form. Even so the traditional 5 x 5 Playfair cipher supports twenty five uppercase alphabets only. To overcome this drawback, various authors have proposed extended Playfair cipher. This paper deals with the study of these variations proposed by different authors on the basis of some parameters.

Cloud computing concept has been envisioned as architecture of the next generation for Information Technology (IT) enterprise. The Cloud computing idea offers with dynamic scalable resources provisioned as examine on the Internet. It allows access to remote computing services and users only have to pay for what they want to use, when they want to use it. But the security of the information which is stored in the cloud is the major issue for a cloud user. Cloud computing has been flourishing in past years because of its ability to provide users with on-demand, flexible, reliable, and low-cost services. With more and more cloud applications being available, data security becomes an important issue to the cloud. In order to make sure security of the information at cloud data storage end, a design and implementation of an algorithm to enhance cloud security is proposed. With a concept, where the proposed algorithm (PA) combines features of two other existing algorithms named Ceaser cipher and Attribute based cryptography (ABC). In this research work, text information are encrypting using “Caesar Cipher” then produced cipher text again encrypted by using proposed algorithm (PA) with the help of private key of 128 bits. And in the last step of encryption process, based on ABC, attribute related to cipher text is stored along with cipher text generated after encryption which provide two-step authentication during decryption process. A security approach is designed and developed for data security concept regarding higher confidentiality and authenticity for the cloud data at cloud storage end with experiment analysis to authenticate its efficiency. From the result analysis it is clearly seen that the proposed technique has better Avalanche Effect and execution time than existing technique and hence can be incorporated in the process of encryption/decryption of any plain text or on any key value.

Security is the biggest concern for any information transferred in the world of Internet. Sometimes sensitive information is communicated via insecure medium so various attacks like Brute force, Crypt analytic are possible for recovering message and key. In recent years, encryption technology has been developed very quickly to secure the transmitted information. Existing techniques have separate mechanism for key distribution and for encryption and decryption at source and destination. As per our best knowledge there is no algorithm that is implemented till now that generates the key and then encrypts the message with that key then transfers the message and the key securely so that the same key can be used for decrypting the message. Still the cipher text remains that of original message length. In this paper we have proposed an efficient cryptographic scheme for text message protection against Brute force and Cryptanalytic attacks. This technique can also be used for most crucial applications where it requires a significant security of transmitted message and also there is no overhead on the transfer of message and the key when it is used with our proposed technique.

In a secret message, cryptography is more directed to the encrypted message while steganography is more directed at the hidden message. However, both methods have the same goal, namely the attempt to conceal the message. On the other side, it turns out the use of cryptography can often be solved / translated by another person or cryptanalyst. This is possible because usually a text message unreadable gives someone suspicion that the text message contains a certain meaning for the owner of the message. Thus, the cryptanalyst attempts to break the encrypted message. While the use of steganography owner of the information is difficult to determine the method or pattern to be formed in composing the message that will be hidden. In this paper, the authors modify the Caesar cipher method that produces ciphertext that can be read. With the ciphertext that can be read, then cryptanalysis not suspicious of the ciphertext. Caesar cipher modification is done by replacing the alphabet into two parts, the vocals were replaced with the alphabet vocal too, and the consonant alphabet was replaced with a consonantal alphabet. However, there are some alphabet consonants are not replaced, this is because the frequency of the alphabet is rarely used in an Indonesian text. From the test results obtained ciphertext that can be read. With the ciphertext that can be read, then the cryptanalyst not suspicious of the message so that the cryptanalyst does not attempt to solve the ciphertext.

With the rise of Python language in these years, more and more developers start to use Python language to do researches. Python language has its own advantage on Encryption algorithm. This paper discusses the principles of Caesar Cipher, Simple Substitution Cipher and Vigenere Cipher and their operating process based on Python, then concludes the characteristics and disadvantages of these Encryption algorithms from security and efficiency. It points out their applicable range, and in the end, forecasts the future of the Encryption algorithm based on Python.

This chapter reviews some examples of several types of concealed communication before asking why concealment might have been of more than practical interest to Anglo-Saxons. The Anglo-Saxon monk Bede describes a substitution cipher in his Reckoning of Time. As well as simple substitution ciphers, Anglo-Saxons used runes to conceal messages, names, and words. One of the more common runic ciphers might better be classed as steganography. As well as demonstrating an interest in runic ciphers, literate Anglo-Saxons seem to have been fascinated by a simple monoalphabetic substitution cipher known as a Caesar alphabet, Caesar cipher, or Caesar shift. We have seen that Isidore of Seville brought the formula for the Caesar shift into the Middle Ages from his reading of the classics. St. Boniface, Anglo-Saxon missionary to the Germans in the eighth century, used substitution ciphers to conceal proper names in his letters. A similar Bonifatian cipher shows up in the Exeter Book's Riddle 36 to muddle Latin words.

Steganography is the art of hiding information in a medium. Steganography tends to leave little doubt about the fact that information is being hidden. In this paper an intelligent approach to image steganography is proposed. First, a key is passed using an algorithm such as Diffie-Hellman. This key is used to encrypt the text using an enhanced Caesar Cipher algorithm which provides security and is extremely quick in terms of speed of execution. Next, this key is divided by 10 to get a single digit remainder, say x. x is then used to determine which pixel value is going to be modulated. x is passed as the parameter to a Fibonacci p-code number system. The output obtained say m is taken as the first pixel to be modulated, afterwards all multiples of m such as 2m, 3m etc are modulated. Once all the multiples of m are completed, the last multiple is taken and divided by 10 and the process is repeated till complete data is hidden.

This paper proposes a new compression technique and compares its performance with the popular adaptive Huffman encoding. The main objective of our approach was to shrink the original data optimally without losing data integrity. The above proposed algorithm employs static variable length non prefix codes for ASCII characters that have been assigned by analyzing the character occurring probabilities in variables lossless data file. We have used several lossless data formats like BMP, PNG, TXT, WAV, FLAC, AAC, WMV, DOC. For comparison and analysis we have used compression ratio, compression time, compression factor and saving percentage. A windows executable application has been constructed to facilitate and ease application usage. Moreover the addition of encryption algorithm(Caesar Cipher) will ensure the file protection and privacy. This compression can easily handle large files and without consuming much of system's resources.

Cryptography is the fascinating science that deals with constructing and destructing the secret codes. The evolving digitization in this modern era possesses cryptography as one of its backbones to perform the transactions with confidentiality and security wherever the authentication is required. With the modern technology that has evolved, the use of codes has exploded, enriching cryptology and empowering citizens. One of the most important things that encryption provides anyone using any kind of computing device is ‘privacy’. There is no way to have true privacy with strong security, the method with which we are dealing with is to make the cipher text more robust to be by-passed. In current work, the well known and renowned Caesar cipher and Rail fence cipher techniques are combined with a cross language cipher technique and the detailed comparative analysis amongst them is carried out. The simulations have been carried out on Eclipse Juno version IDE for executions and Java, an open source language has been used to implement these said techniques.

Thousands of years proved that Cryptography and encryption is been used for secure sheltered communication. The word Cryptography comes from the two Greek words Kryptos means hidden and Graphein means writing. Cryptography, the use of codes and ciphers to protect secrets, since from the ancient times various cryptographic techniques where as symbols used by Egypt, Spartans developed a device called Scytale used by Greece, Julius Caesar developed the Substitution cipher technique for the purpose of military used by Rome, Leon Battista Alberti invented a cipher disk which acts as an encryption system called Vigenere Cipher, Thomas Jefferson invented Wheel Cipher consisting of 26 wheels. Similarly, rulers invented War Driven Cryptography to meet with the outcome of war. Modern cryptographic techniques proves that it is been the trendsetter which ensures high security than ancient times and War Driven Cryptography. To protect a valuable information people develop better ways through a thorough understanding of cryptography and encryption which makes technology more efficient and faster.

This study combines classic and modern cryptographic algorithms so that the data security of information more awake authenticity. Caesar cipher is the oldest classical cryptography which uses a symmetric key method is the key used for encryption is the same as the key used for the decryption process. Three-Pass Protocol is one of the modern cryptography where the process of sending a message does not need to distribute the key so that each party both the recipient and sender of the message does not need to know each lock. In this combination of receiving and sending messages using the Caesar Cipher algorithm for encryption and decryption, while for its delivery process using algorithms Three Pass protocol. The results from the combination of the two algorithms are to help the information sent is secure.

A cypher (or encryption) is a method of transforming a message into a set of alternate characters that conceals the contents of the message. The Caesar cypher (or shift) was one of the earliest cyphers ever used. More than two thousand years ago, Julius Caesar was able to convey secret messages to his generals and colleagues.

Today is a typical day. Waking up is difficult because you had a very long day yesterday, and worked well into the evening. At least you have a beautiful view this morning, as the rising sun glints off the Jemez Mountains. Drinking your government-issued coffee with your breakfast, you decided that this will be a two-cup morning, because today is going to be a long one, too. Walking from your home to work means a stop at the security checkpoint. After showing the guard your credentials, you walk to your building in the secure area, then to your desk, where you will sit, along with row after row after row of other women with similar desks, spending the day doing mathematical calculations.

Cipher is a first polygraphic substitution cipher that works on digraphs, trigraphs (3 letter squares) or hypothetically blocks of any magnitude. The Hill Cipher utilizes a region of science called Linear Algebra, and specifically requires the client to have a rudimentary knowledge of matrices. It additionally makes utilization of Modulo Arithmetic (like the Affine Cipher). To perform decryption, the hill cipher requires the inverse of the key matrix. This is the major shortcoming of Hill cipher since every key matrix is not invertible. We will propose a new variant of hill cipher, which will find the decryption of the cipher text even when the key matrix is non invertible.

Character type cipher is always used in web application system and can be deciphered by the illegal users through "run dictionary", so, a new random encryption algorithm for character type cipher is put forward in this paper. The encryption parameters are randomly generated in the algorithm, and random confusion is adopted in the cipher text structure, so the same plaintext can produce different ciphertexts.the experimentation shows that the algorithm is feasibility and validity.

Data transmission has become very common in human's daily life. This data transmission can be confidential or the data may be intended for a section of people. The data that is intended to be transmitted to a particular recipient should be read only by the corresponding person and not anyone else. For this reason, the best way to protect the data is by encryption. This provides security from stealing of data. This paper deals with a mechanism to encrypt a data using flip-flops and double substitution method. The basic idea to obtain blocks of plain text and then use T-flip-flops along with double substitution to result in a convincing cipher text. The result is a cipher text obtained by using plaintext itself for encryption. This algorithm can be used to transmit bit sequence of any length, thus ensuring the usage of bandwidth to desirable level. This method may result in an Electronic Code Book (ECB). The keys used will be asymmetric. The receiver just follows the steps in reverse order to retrieve the data or plaintext from the received cipher text.

Cryptography subject is part of the curriculum of the Bachelor’s Degree in Computer Engineering in Information Systems, at the University of Salamanca. This subject becomes easy to understand if the history of Cryptography is used. The basic mathematics includes the following main topics: Modular arithmetic, algebraic curves, finite fields and number theory. Cryptography is a means of protecting personal information to avoid an eavesdropper can access it. From the first century AD with the Julius Caesar cipher to the present day with RSA, ElGamal, knapsack or elliptic curve cryptosystems, the Cryptography has evolved. In this paper we will show the syllabus of Cryptography subject and how the history knowledge supposes an important part of it, and helps students to acquire the skills and competences included in the subject curriculum.

Purpose Fast, quantitative T2 mapping is of value to both clinical and research environments. However, many protocols utilizing fast spin echo (FSE) pulse sequences contain acceleration-induced artifacts that are compounded when fitting parameter maps, especially in the presence of imperfect refocusing. This work presents a B1-corrected, model-based reconstruction and associated Cartesian FSE phase-encode ordering that provides enhanced accuracy in T2 estimates compared with other common accelerated protocols. Theory and Methods The method, known as multiple echo, Caesar cipher acquisition and model-based reconstruction (ME-CAMBREC), directly fitted T2, flip angle, and proton density maps on a row-by-row basis to k-space data using the extended phase graph model. Regularization was enforced in order to minimize noise amplification effects. ME-CAMBREC was evaluated in computational and physical phantoms, as well as human brain, and compared with other FSE-based T2 mapping protocols, DESPOT2, and parallel imaging acceleration. Results In computational, phantom, and human experiments, ME-CAMBREC provided T2 maps with fewer artifacts and less or similar error compared with other methods tested at moderate-to-high acceleration factors. In vivo, ME-CAMBREC provided error rates approximately one-half those of other methods. Conclusion Directly fitting multi-echo data to k-space using the extended phase graph can increase fidelity of T2 maps significantly, especially when using an appropriate phase-encode ordering. Magn Reson Med 73:1065–1074, 2015. © 2014 Wiley Periodicals, Inc.

In the modern world as there is drastic hike in use of internet for our daily work there is need to keep our information safe and secure so that an intruder can't misuse it. Cryptography was established to solve this problem. Cryptography is an art of transforming information (Plain Text) using encrypting algorithms into a form that is not readable (Cipher Text) without access to specific decoding algorithms. In this paper the author presents a novel approach to cryptographic techniques and illustrates the result and analysis of the proposed algorithm and points out that it is with improved security from many kind of attacks. This paper is partitioned in following sections: 1 st section contain basic introduction about cryptography and Caesar Cipher, 2 nd section includes proposed system, 3 rd contain performance analysis where proposed system is compared with other techniques, 4 th include Conclusion and Future Scope and last section contains

Cryptography is an art and science of converting original message into non readable form. Fast progression of digital data exchange in electronic way, information security is becoming much more important in data storage and transmission. Cryptography has come up as a solution which plays a vital role in information security system against malicious attacks. In this project, encryption will be implemented information that makes it hard to be readable and secure. For that matter, encryption method known as Caesar cipher, one of the simplest and most widely used encryption techniques. In this encryption, it uses the three methods in which each letter in the plaintext is replaced by some fixed number of position down the alphabet. The result from this project is a data which is encrypted and be decrypted to its readable form. As a conclusion, Caesar cipher algorithm can be implemented in many encryption projects to make data secure and better.

Exchange of information through the medium of the internet allows information can be accessed by unauthorized parties. Techniques for securing information that is commonly used is Cryptography. This research will use a combination of two classic algorithms which are Columnar Transposition Cipher and a Caesar Cipher with a Linear Congruential Generator modification. Information in the form of images often has some of the same pixel value components. For saving the memory then the writers use the technique of compression with Lempel Ziv Welch algorithm, which is a dictionary-based compression algorithm. Stages of the process used in this study are that the pictures will be encrypted using the algorithm of Columnar Transposition Cipher, next step the file that has been encrypted will be encrypted with the Caesar Cipher algorithm using a combination of and Linear Congruential generators are modified. Then the image file that has been encrypted will be compressed using the second algorithm Lempel Ziv Welch. For the implementation of programming language C # systems used. The results of this study showed that the combination of Columnar Transposition Cipher and a Caesar Cipher with a Linear Congruential Generators could keep the confidentiality, integrity, and security of data. Lempel Ziv Welch algorithm produces the value of the average compression ratio (RC) 67.05%, in Compression Ratio (CR) aspect the value is 1.49, and in Space Saving (SS) parameter, the percentage is 32.93%.

Key-based security is still the most widely used form of security today with a key distribution process between senders and receivers that is commonly perform and also it is a classic problem in cryptography where key must be share to other parties (sender or receiver) and its maybe known when third parties do sniffing process or man in the middle attack. Three-Pass Protocol is one solution that can be used to overcome the problem of key distribution, because the sender and receiver can encrypt and decrypt without need to exchange keys. Security in Three-Pass Protocol uses XOR logic so that the resulting ciphertext will be very easy to decrypt by those who are not responsible, to improve data security in the Three-Pass Protocol process which is use Caesar Cipher and Vigenere Cipher algorithms in the encryption and decryption process in the Pass Protocol scheme, and ciphertext encryption results are quite difficult to read and require a long time to decrypt them.

At this time, the advancement technology of computer science and telecommunications are developed highly and progressing rapidly. Data security is very important to maintain the important data content of the parties that can harm by destroying important data from the data owner. By improving data security, using a combination of algorithms, it can keep data security more secure than attacks that can harm the content of stored data, especially data in the form of document files and text messaging. The combination of algorithms used for data security used is caesare cipher algorithm and RSA algorithm. So by using a combination of caesar cipher algotitm and RSA algorithm, the security level of document files and text messages can be more awake the authenticity of the data.

Serial number of operating system windows 7 needs to be safeguarded, so can’t be used by the others. Security of the data can use by modern cryptography such as Vernam Cipher methods and classic cryptography such as Caesar Cipher methods. The security level both of this method depends on the keywords used and it will difficult to crack if the random key is used more and more. To get a random key, we can take from chaos of Lorenz equations as key-generator for encryption and description. Before utilizing chaos in the Lorenz equations, we have to find the maximum t (time) for the inverse problem solution to fit with the forward problem solution. We can use Runge-Kutta method in the Lorenz equations for forward problem solution and inverse problem solution. The solution of integral that obtained by the Runge-Kutta method can be searched by Trapezoidal method. The result of Runge-Kutta solution and Trapezoidal will be used as key-generator for encryption and description. In the simulations performed, the best orde in Runge-Kutta method is 4 and t max is 2. The encryption key is used as the initial condition of Lorenz equation, then the result is integrable by the Trapezoidal method. The result of orde 4 from Runge-Kutta method and Trapezoidal method used as a key-generator. Application of Lorenz equation as key-generator for encryption and decryption, may change the cryptography algorithms of symmetric to be asymmetric.

This article presents Christian ciphers counterparts of the well-known Hebrew atbah cipher used in main languages and scripts of the Christan Orient: in Greek, Coptic, and Syriac, in Late Antiquity and the Middle Ages. The article also describes other alphabetic substitution ciphers used in these languages and highlights numerical rules in their construction.

Cryptography is an art and science of converting or iginal message into non readable form. There are tw o techniques for converting data into no readable form:1)Transposition techniqu e 2)Substitution technique. Caesar cipher is an exa mple of substitution method. As Caesar cipher has various limitations so this ta lk will present a perspective on combination of tec hniques substitution and transposition. In this paper I have focused on the well known classical techniques the aim was to ind uce some strength to these classical encryption for that purpose I blended cl assical encryption with the some more techniques. m y proposed method showed that it is better in terms of providing more security tany given text message. In our experiments I took Caesaer Ciphers as representatives of Classical Techniques. To make it more secure I have used some techniques like I hav e used multiple level Row Transposition Ciphers, encryption with same key at each level an d encryption with different key at each level.

The confidential information that sent via an insecure communication channels like the internet, have a greater risk to be tapped by the parties are not entitled to know the confidential information. One of the things that can be done is to encrypt information into code that can not be understood. Art and science to keep the confidentiality of information is called cryptography. Historically, cryptography has been used since ancient Roman times, world war, until the digital age and information technology as it is today. From the beginning of its development, the method used for the encoding process using simple calculations. Along with the development of technology, the methods used are also growing, such as the use of computers with mathematical calculations are complicated. One area of ??Mathematics that has a very important role in cryptography is algebra. Many of the methods used in cryptography using algebraic operations are defined over an algebraic structure, as in the group, ring and field. In this paper, its discussed about several applications of algebra that used in cryptography, especially on the structure of algebra (abstract algebra) and linear algebra. Given cryptographic method is Caesar cipher, shift cipher, permutation cipher, Hill cipher, ElGamal and RSA.

The Caesar Cipher algorithm for cryptography is one of the oldest algorithms. Now much newer algorithms have arrived that are much more secure, however in terms of speed of execution Caesar cipher algorithm is still the fastest owing to its simplicity. However the algorithm is extremely easy to crack. This is because in this algorithm each character of a message is always replaced by the same fixed character that has been predetermined. To improve the algorithm and enhance it's security feature, a few changes can be added. This paper proposes an enhancement to the existing algorithm by making use first of a simple Diffie-Hellman key exchange scenario to obtain a secret key and later using simple mathematics to ensure the encryption of data is much more safer. Once a private shared key is obtained by making use of the Diffie-Hellman method, the key is subject to the mod operation with 26 to obtain a value less than or equal to 26, then the current character is taken and to this the key value obtained is added to obtain a new character. For any character in the ‘x’ position the key is simply first multiplied with ‘x’ and then mod is done to obtain the encrypted character. So 2nd character of the message is multiplied with 2, third character with 3 and so on. This enhances the security and also does not increase the time of execution by a large margin.

Cryptography is the science of writing in secret code. In substitution algorithms known to us there are keys which decide the cipher text of every letter we want to transmit and these cipher texts remain constant throughout the message. So, when such algorithms are used to encrypt long messages, an attacker may easily find out and note down the common 2-letter or 3-letter words used and with the help of those letters and some brute force he will be able to decrypt the entire message. To overcome this crisis or this drawback we have come up with a solution SET REPLACEMENTS technique. Set Replacements technique is a substitution algorithm which allows you to have a different cipher text for every instance of the same letter i.e. every time you use a letter which is repeated twice or thrice in the word, it will have a different cipher text replacing it on its every instance. This will ensure that the attacker will not be able to note down the repeatedly used words or common words and decrypt the entire message using those key words and some brute force, thus securing the confidentiality of the message to its roots.

2D advance playfair technique for generating more secure cipher text. Diagraph (combination of 2 characters) of the plaintext are treated as single unit and converted into corresponding cipher text Diagraph and vice-versa. Classical Playfair Cipher supports English alphabets with limitation that only one alphabet “i” or “j” will be considered at a time. 2d advance Playfair Cipher came into focus to eliminate this limitation.2d advance Playfair cipher supports all 26 English upper alphabets {A-Z}, lower alphabets [a-z], 10 digits {0–9} and 28 special characters including {! “ ∗ # $ % & ‘ +, −. /:; ( ) ? @ [ ] \ ⁁ _ I }. For enhance the security, use the diffie-hillmen key exchange algorithm with the advanced substitution encryption techniques to provide security. 2d advance Playfair Cipher use for enhance the security of text files that contains alphabets, numerals and special characters.

Submitted by LEANDRO RODRIGUES DE CARVALHO null (leandrorodca@gmail.com) on 2016-05-20T19:48:46Z No. of bitstreams: 1 dissertacao-Leandro-profmat-2016.pdf: 1207301 bytes, checksum: 3605d67341c1a33446dc9c537f6b735e (MD5) Rejected by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br), reason: Foram realizadas suas submissões. Favor submeter novamente apenas uma vez com o arquivo correto. on 2016-05-24T14:34:08Z (GMT) Submitted by LEANDRO RODRIGUES DE CARVALHO null (leandrorodca@gmail.com) on 2016-05-25T10:37:49Z No. of bitstreams: 1 dissertacao-Leandro-profmat-2016.pdf: 1207301 bytes, checksum: 3605d67341c1a33446dc9c537f6b735e (MD5) Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-05-25T19:03:01Z (GMT) No. of bitstreams: 1 carvalho_lr_me_rcla.pdf: 1207301 bytes, checksum: 3605d67341c1a33446dc9c537f6b735e (MD5) Made available in DSpace on 2016-05-25T19:03:01Z (GMT). No. of bitstreams: 1 carvalho_lr_me_rcla.pdf: 1207301 bytes, checksum: 3605d67341c1a33446dc9c537f6b735e (MD5) Previous issue date: 2016-04-28 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) O grande desafio no ensino da matemática, pelo menos no meu ponto de vista como professor nos últimos dez anos, é fazer com que os alunos percebam a importância e a praticidade da matemática em suas vidas. Isso vai além das teorias da Aritmética, Álgebra ou Geometria ensinadas na educação básica. Os alunos precisam perceber que os conceitos matemáticos são ferramentas que os ajudam a compreender o mundo a sua volta. Diante disto, esta dissertação busca apresentar conceitos matemáticos que levam à compreensão da Criptografia: conceitos da Teoria dos Números e da Álgebra. Fazemos ainda, um breve histórico sobre a Criptografia descrevendo a cifra de César e as cifras afins, o Sistema RSA e alguns métodos de troca de chaves. Relatamos alguns trabalhos desenvolvidos pelos estudantes do PROFMAT neste tema e apresentamos uma proposta de atividade para os estudantes do ensino básico. Esta atividade consiste na construção de um kit de encriptação e decriptação utilizando copos descartáveis. Com dinâmicas unindo elementos da Criptografia e o aplicativo Whatsapp, como meio de troca das mensagens criptografadas, motivamos a sala de aula para o aprendizado da Divisão Euclidiana e da Permutação. Além disso, pretendemos despertar nos alunos o interesse em aprofundar-se nos estudos da Matemática, principalmente na Teoria dos Números, já que esta é uma das ferramentas fundamentais no contexto da Criptografia, uma ciência com grande aplicabilidade na atualidade. The great challenge in teaching mathematics, at least in my point of view as a teacher in the past ten years is to make students understand the importance and practicality of mathematics in their lives. This goes beyond the theories of arithmetic, algebra or geometry taught in basic education. Students need to realize that mathematical concepts are tools that help them understand the world around them. In view of this, this dissertation aims to present mathematical concepts that lead to understanding of cryptography: concepts of number theory and algebra. We also a brief history on the Encryption describing the Caesar cipher and related figures, the RSA system and some methods of key exchange. We report some work done by students PROFMAT this theme and present a proposal activity for students of basic education. This activity consists in building a kit of encryption and decryption using disposable cups. With dynamic linking elements Encryption and Whatsapp application as a means of exchange of encrypted messages, we motivate the classroom for learning Euclidean division and permutation. In addition, we intend to arouse students' interest in deepening the study of mathematics, especially in Number Theory, as this is one of the fundamental tools in the context of cryptography, a science with great applicability today.

In the recent years the need of security has increased many folds. It's not that the need to secure data is new and goes back to the time of 1st and 2nd world war and even back to the time of Caesar. This paper gives a history of all the data hiding techniques used in the history and how these techniques have evolved from Caesar cipher to DES and then to Triple-DES, AES and current algorithms. This paper will explain the pros and cons of previous algorithms and why they are not used now a day. The scope of this paper will go from general data hiding techniques and then moves to cryptographic algorithms.

Cryptography is used widely for the purpose of secure communication and password management. It comprises the techniques of encryption and decryption mechanism. Using the encryption mechanism a plaintext is converted into a cipher text and in decryption with the help of a secure key the encrypted message is decoded into a plain text. Mathematical principles can be employed for encryption determinants to encrypt and decrypt our message and to transmit them securely. In this paper we are using principles of Caesar cipher and Hill Cipher and developing an encryption and decryption algorithm to make transmission of messages secure from eavesdropping.

Secured Communication involves Encryption process at the sending end and Decryption process at the receiving end of the communication system. Many Ciphers have been developed to provide data security . The efficiency of the Ciphers that are being used depends mainly on their throughput and memory requirement. Using of large key spaces with huge number of rounds with multiple complex operations may provide security but at the same time affects speed of operation. Hence in this paper we have proposed a method to improve Caesar cipher with random number generation technique for key generation operations. The Caesar cipher has been expanded so as to include alphabets, numbers and symbols. The original Caesar cipher was restricted only for alphabets. The key used for Caesar Substitution has been derived using a key Matrix Trace value restricted to Modulo 94. The Matrix elements are generated using recursive random number generation equation, the output of which solely depends on the value of seed selected . In this paper, we made an effort to incorporate modern cipher properties to classical cipher. The second stage of encryption has been performed using columnar transposition with arbitrary random order column selection. Thus the proposed Scheme is a hybrid version of classical and modern cipher properties. The proposed method provides appreciable Security with high throughput and occupies minimum memory space. The Method is resistant against brute-force attack with 93! Combinations of keys, for Caesar encryption.

In this paper conventional Playfair Cipher is being modified by encrypting the plaintext in blocks. For each block the keyword would be the same but the matrix will shift by some random value. As a result of which the diagram analysis would be very difficult which is done in the traditional Playfair Cipher to obtain the plaintext from the ciphertext. The shift value will be generated using SHA-1 which is very secure. Playfair Cipher method, based on polyalphabetic cipher is relatively easy to break because it still leaves much of the structure and a few hundred of letters of ciphertext are sufficient. To add to its security and to make it more usable we are using 6x6 matrix instead of 5x5 which will be able to cover 26 alphabets in English and ten numerals i.e. from 0 to 9. This 6x6 matrix eliminate the case of putting of 2 alphabets (I and J) together in the matrix as it was in the 5x5 matrix. Plaintext as well as key can be numeral, alphabetic or combination of both.

In this paper the authors present a new integrated symmetric-key cryptographic method, named SJA, which is the combination of advanced Caesar Cipher method, TTJSA method, Bit wise Rotation and Reversal method. The encryption method consists of three basic steps: 1) Encryption Technique using Advanced Caesar Cipher, 2) Encryption Technique using TTJSA Algorithm, and 3) Encryption Technique using Bit wise Rotation and Reversal. TTJSA Algorithm, used in this method, is again a combination of generalized modified Vernam Cipher method, MSA method and NJJSAA method. Nath et al. already developed some symmetric key encryption methods namely MSA, DJSA, DJJSA, modified DJJSA, NJJSA, TTJSA, TTSJA, DJMNA, UES-I, UES-II etc. The cryptanalysis shows that TTJSA is free from standard cryptographic attacks such as differential attack, plain text attack or any brute force attack. In the present method the authors have used advanced modified Caesar Cipher method where the authors have modified the standard Caesar Cipher method and then they applied TTJSA method to make the entire crypto system very hard to break. The present method has been tested on different plain text specially with repeated character and the spectral analysis of the plain text and the encrypted is also been shown. The spectral analysis shows that the present cryptography method, SJA can not be broken with any kind of standard cryptography attack. The authors propose that the present method will be most suitable for password, SMS or any kind of small message encryption.