# Symmetric Key Cryptography

## Top PDF Symmetric Key Cryptography:

### Enhanced Content Based Double Encryption Algorithm Using Symmetric Key Cryptography

This paper aims to solve the problems of the existing technique of the content based double encryption algorithm using symmetric key cryptography. Simple binary addition, folding method and logical XOR operation are used to encrypt the content of a plaintext as well as the secret key. This algorithm helps to achieve the secure transfer of data through the network. It solved the problems of the existing algorithm and provides a better solution. The plaintext are encrypted using the above methods and produce a cipher text. The secret key is encrypted and shared through secure network and without knowing the secret key it is difficult to decipher the text. As per expected, enhanced encryption algorithm gives better result than the existing encryption algorithm.

### Key Distribution for Symmetric Key Cryptography: A Review

Cryptography is the art of achieving security by encoding messages to make them non-readable [1]. Cryptography not only protects the information but also provides authentication to the user. Here the original information and encrypted information are referred as plaintext and cipher text respectively. The transformation of plaintext into unintelligible data known as cipher text is the process of encryption. Decryption is the reverse process of encryption i.e. conversion of cipher text into plain text. During communication, the sender performs the encryption with the help of a shared secret key and the receiver performs the decryption. Cryptographic algorithms are broadly classified as Symmetric key cryptography and Asymmetric key cryptography. In symmetric key cryptographic algorithms single key is used for both encryption and decryption process [1]. Fig 1.1 illustrate that the general procedure for symmetric key cryptography.

### A Modified Approach for Symmetric Key Cryptography Using Circles

ABSTRACT: Cryptography is the science or art of transforming an intelligible message(plaintext) into one that is unintelligible(cipher text) and then transforming the message back to its original form. . Symmetric key Cryptography is a cryptographic approach where the sender and receiver of a message share a single, common key that is used to encrypt and decrypt the message Geometry based cryptography is a new and emerging approach in the field of cryptography. It uses geometric shapes such as circles, ellipses etc and perform geometric transformations on these figures to produce cipher text. The presented work focuses on the Symmetric key Cryptography technique, using the concepts of Cartesian coordinate geometry and circle generation. Chakra algorithm, for symmetric key cryptography, is used as the basis for this work with some modifications in it for better results. Chakra is a Sanskrit term which means a circle or a disc. It plays a key role in encryption of data. Data is grouped into circles and each circle holds a portion of data. An improved geometric cryptographic algorithm is developed, that considers data into a 2- dimensional data grid, generate circles on the grid and apply some geometric transformations over data. This encryption technique adapts hybrid geometric transformations,(i.e., translation followed by scaling ) of the circumference points of every circle by some scaling factors(S,Sy) and translation factors(Tx,Ty). The proposed algorithm is an improvement in the basic Chakra algorithm in terms of accuracy.

### Frame Based Symmetric Key Cryptography

Cryptography, a word with Greek origins, means “secret writing”. However, we use the term to the science and art of transforming messages to make them secure and immune to attacks. The original message, before transformed, is called plaintext. After the message is transformed, it is called cipher text. The process of encoding plain text messages into cipher text messages is called encryption. The reverse process of transforming cipher text messages back to plain text is called decryption. If the same key is used for encryption and decryption, we call the mechanism as Symmetric Key Cryptography. Cipher text = encrypt (plaintext, key),Plaintext = decrypt (cipher text, key). If two different keys are used in a cryptographic mechanism, wherein one key is used for encryption, and another, different keys are used for decryption; we call the mechanism as Asymmetric Key Cryptography.

### Title: Symmetric Key Cryptography: Current Trends﻿

Cryptography is the study of information hiding and retrieval. Cryptography is derived from the Greek words: kryptós, "hidden", and gráphein, "to write" - or "hidden writing". It is the art of protecting the information by transforming it into an unintelligible format in which a message can be hidden from reader and only the intended recipient will be able to convert it into original message. All intruders or unauthorised readers can only see gibberish. Its main goal is to keep the data safe from unauthorized access. It includes the guidelines, algorithms and methodologies to safely and consistently prevent or delay unauthorized access to vital information and helps verify all components in a communication. Individuals who examine and create cryptography are called cryptographers. The investigation of how to evade the utilization of cryptography for unintended beneficiaries is called cryptanalysis, or code-breaking. Cryptography and cryptanalysis are once in a while gathered together under the umbrella term cryptology,

### A Two Round Block Cipher Symmetric Key Cryptography based on Key Stream

In other words, an encryption scheme must have the property that decrypting a cipher text (with the appropriate key) yields the original message that was encrypted. Recapping our earlier discussion, an encryption scheme would be used by two parties who wish to communicate as follows. First, Gen is run to obtain a key K that the parties share. When one party wants to send a plaintext m to the other, he would compute c: = Enck(m) and send the resulting cipher text c over the public channel to the other party. Upon receiving c, the other party computes m: = Deck(c) to recover the original plaintext. In a nutshell, mathematically a cryptosystem is a 5- tuple(P,K,C,E,D), where P is the set of plain-texts, K is a set of keys, c is the set of cipher texts, E:P x K C is the set of enciphering functions, and D:C x K P is the set of deciphering functions.

### Symmetric Key Cryptography using Dynamic Key and Linear Congruential Generator (LCG)

Cryptography is probably the most important aspect of communication security and is becoming increasingly important as a basic building block for computer security. The increased use of computer and communication systems by industry has increased the risk of theft of proprietary information.To avoid this one has to send the encrypted text or cipher. Cryptography is now an emerging research area where the scientists are trying to develop some good encryption algorithm so that no intruder can intercept the encrypted message. Symmetric encryption also referred to as conventional encryption or single key encryption, was the only type of encryption in use in 1970s. Symmetric-key (SK) cryptography can broadly be divided into three classes: stream ciphers, block ciphers and hash functions (including MAC algorithms). Stream ciphers and block ciphers are used to achieve data confidentiality. Hash functions and MAC algorithms are used respectively for integrity and authentication. This paper proposes a method for encryption & decryption using secret dynamic key. For every pair of encryption & decryption a new key is generated. The rest of the paper is organized as follows: Section 2 gives a brief introduction to cryptography, linear congruential generator, dynamic key, one time pad. Section 3 describes the proposed approach. Section 4 shows the comparative performance analysis. Section 5 concludes the work.

### An Enhanced Symmetric Key Cryptography Algorithm to Improve Data Security

By using symmetric encryption approach. The symmetric encryption approach is divided in to two types one is block cipher symmetric cryptography technique and another is stream cipher symmetric cryptography but here block cipher type is used because its efficiency and security is good as compared to other. Proposed technique uses a common key between sender and receiver, which is known as private key. Basically private key concept is the symmetric key concept, where plain text is converted into encrypted text known as cipher text using private key and cipher text is decrypted by same private key into plain text. The encryption key is trivially related to the decryption key, in that they may be identical or there is a simple transform to go between the two keys. The keys, in practice, represent a shared secret between two or more parties that can be used to

### A Novel Symmetric Key Cryptography using Multiple Random Secret Keys

Symmetric key cryptography schemes are categorized into either stream ciphers or block ciphers. Stream cipher operates on a single bit at a time, and for each bit a different key is generated. In general, the same plaintext will encrypt to the different ciphertext in a stream cipher [6]. Stream ciphers come in two worth mentioning flavors i.e. Self-synchronizing stream ciphers and Synchronous stream ciphers. Each bit in the keystream is calculated as a function of the previous n bits in the keystream by the Self-synchronizing streamciphers. Since, the decryption process stay synchronized with the encryption process by knowing how far it is into the n-bit keystream, it is termed as "self-synchronizing". The keystream generated by the Synchronous stream ciphers is independent of the message stream but uses the same keystream generation function at sender and receiver. Stream ciphers do not propagate transmission errors and are periodic in nature, so that the keystream will eventually repeat. P = Plaintext; K = Secretkey; C = Ciphertext; E = Encryption

### Musical Cryptography Using Multiple Note Substitution Algorithm

Musical cryptography techniques convert the plain text message into musical notes or musical symbols. Musical cryptography uses music and its features to encode the message into a cipher message. The main task in the musical cryptography is to generate musical cryptograms which in turn are good sequence of musical patterns soothing to ear. The traditional methods used in musical cryptography limits the length of the plaintext to be encrypted. In this paper, a multiple note substitution algorithm based symmetric key cryptography is proposed to overcome the limitation to the number of letters in plaintext.The application of the algorithm produce cryptic message which not only hide the message as musical piece but it also reduces the chance of cipher message to be detected as cipher.

### Efficiency key generation management in a big organization for symmetric cryptography system

Nowadays big organizations have complex administrative structure with scattered offices to face with serious problems related to key management like financial and security problems based on symmetric encryption system. This project proposes an efficient solution related to symmetric key crypto system to solve this problem and provide the opportunity for the organization have a secure, affordable, efficient, easier and faster symmetric key crypto system. Symmetric key cryptography with the less key size have more secure in comparison to asymmetric cryptography. Therefore using symmetric key cryptography is more secure and Advantageous. The speed of processing symmetric cryptography is higher than asymmetric cryptography. The purpose of this project is to product the software for all of the employees in the organization to have the secret symmetric key cryptography to have communicatation to each other through the secret key. However, the security of symmetric key cryptography is higher than asymmetric key cryptography. Key derivations algorithm which used in this project is very important for symmetric cryptosystems in comparison with other algorithm because one key can be derived to the others. This Method is chosen by key derivation one-way function and implemented by Delphi programming language. This implemented method give the manager of the organization an opportunity to generate the secret key for all of the employees and so each employee has the symmetric secret key and if the employees need to communicate with each other their request will be sent to the manager. This project has been done in three phases and one of the outcomes of this project is an application which generates random key, according to hierarchy of organization.

### Public Key Infrastructure (PKI) using Symmetric Key Cryptography (SC) in VANETs

Abstract— Vehicular Ad-Hoc Network (VANETs) provides the vehicle to vehicle (V2V) communication for the safety application. There are many security requirements in VANETs. ECDSA algorithm fulfils all the security requirements but it’s come with the processing overhead and there is a chance of computation based DoS attack. However the VANETs are the time constrained each safety message should be reached at a time to other vehicles. TESLA uses the symmetric key cryptography that is MAC algorithm but it is not that much scalable as compared to ECDSA because of multi-hop communication is not possible in TESLA and also it uses the delay key disclosure so till that the message and MAC has to be stored in the memory so there is chances of memory based DoS attack in TESLA. So if we use the MAC algorithm in the classical PKI system in place of ECDSA algorithm than it can reduce the processing overhead associated with ECDSA so time will be low for each message authentication and it also mitigate the problem of memory based and computation based DoS attacks that can be useful for the VANETs safety related applications as safety applications are time constraint.

### Data security in cloud storage using Advanced Encryption Standard and Honey Cryptography

In Cloud computing, data security has an important role in the communication system development. Network security has become a major concern in the recent years because, in cloud storage environment, the data should be secured from the intruders. So the data should be encrypted and outsourced in the cloud. Cryptography serves an important role in the information security system against different attacks and cloud storage systems. New types of cryptography techniques can overcome the security threat. The Advanced Encryption Standard is a robust symmetric key cryptographic algorithm that uses the lookup table to enhance its performance. The Cache Timing Attack relates the encryption timing details under a key already known with a key that is unknown to infer the key that is unknown. Here an extension of a public-key cryptosystem is proposed which is a combination of Advanced Encryption Standard and Honey Cryptography to support a private key cryptosystem. The results have been obtained by Advanced Encryption Standard key length as 128 bit and no. of iterations as 10.To improve competency and to reduce drawbacks, this paper proposes a honey encryption scheme. The parameters to be discussed focuses on the no. of iterations, key length, and the side channel attack type to be implemented. Keywords: cloud computing, symmetric key cryptography algorithm, data security, advanced encryption standard and honey

### Cryptography Algorithms : A Review

Cryptography is derived from Greek word . It has 2 parts: 'crypto' means "hidden, secret" and 'graphy' means "writing". It is a study of techniques for secure communication in the presence of third parties to maintain information securities such as data integrity, confidentiality , authentication, and non-repudiation. It is an art to transform the messages to make them secure and immune against security attacks. The art of protecting information by transforming into an unreadable format, called cipher text or decrypt the message into plain text. The cipher text is only understood by someone who only knows how to decrypt it. The information is encrypted using an encryption algorithm, which specifies how the message is to be encoded. Any intruder that can see the cipher text should not be able to determine about the original message. Only an authorized party is able to decode the cipher text which requires a secret decryption key.

### Secure Cloud Environment Using RSA Algorithm

become a major issue. encryption and decryption data have recently been widely investigated and developed because there is a demand for stronger encryption and decryption which is very hard crack. cryptography plays major roles to fulfillment these demands. now days, many of researcher have proposed many of encryption and decryption algorithm such as AES, DES, RSA, and others. an RSA system generally belongs to the category of pkcs . rsa encryption is one of the public-key method that have been popular, the rsa algorithm is used in many application. although the security of rsa is beyond doubt, the evolution in computing power has caused a growth in the necessary key length. the performance characteristics of rsa are observed by implement the algorithm for computation. in this paper, RSA was implemented through an asymmetric key algorithm ,encryption and decryption procedure over different key size.

### Volume 2, Issue 3, March 2013 Page 72

Network security is a complicated subject, historically only tackled by well-trained and experienced experts. However, as more and more people become ``wired'', an increasing number of people need to understand the basics of security in a networked world. This document was written with the basic computer user and information systems manager in mind, explaining the concepts needed to read through the hype in the marketplace and understand risks and how to deal with them. Some history of networking is included, as well as an introduction to TCP/IP and internetworking. We can consider risk management, network threats, firewalls, and more special-purpose secure networking devices. This is not intended to be a ``frequently asked questions'' reference, nor is it a ``hands-on'' document describing how to accomplish specific functionality. It is hoped that the reader will have a wider perspective on security in general, and better understand how to reduce and manage risk personally, at home, and in the workplace. Cryptography and Network Security Does security provide some very basic protections that we are naive to believe that we don't need? During this time when the Internet provides essential communication between tens of millions of people and is being increasingly used as a tool for commerce, security becomes a tremendously important issue to deal with. There are many aspects to security and many applications, Ranging from secure commerce and payments to private Communications and protecting passwords. One essential aspect for secure communications is that of cryptography. Cryptography is the science of writing in secret code and is an ancient art. The first documented use of cryptography in writing dates back to circa 1900 B.C. when an Egyptian scribe used non-standard hieroglyphs in an inscription. In data and telecommunications, cryptography is necessary when communicating over any untrusted medium, which includes just about any network, particularly the Internet. Within the context of any application-to-application communication, there are some specific security requirements, including:

### Multipair Public Key Cryptosystem

Present days, security is required to transmit confidential information over the network. Security is also required in a wide range of applications. Internet is frequently used to upload web pages and other documents from a private development machine to public webhosting servers. Transfer of files from one place to another place, like banking, e- transactions, e-shopping, e-business, and tenders etc. need special authenticated mechanism. As a communications and transmission of files over internet Present days, security is required to transmit confidential information over the network. Security is also required in a wide range of applications. Internet is frequently used to upload web pages and other documents from a private development machine to public webhosting servers. Transfer of files from one place to another place, like banking, e-transactions, e-shopping, e-business, tenders etc need special authenticated mechanism. As a communications and transmission of files over internet has increased exponentially since last few years, there is need of security in such file transfer. Most recommended solutions to secure communication is cryptography. Cryptography is an act of writing in code or cipher. Information that can be read and understood without any special measures is called plaintext or clear text. The method of concealing plaintext in such a way as to conceal its substance is called encryption. Encrypting plain text outcomes in unreadable hideous form called cipher text. Cryptography plays a gorgeous role in providing the data security against malicious encroach. It is the art of protecting the information by transforming it into an unreadable format in which a message can be invisible from the casual reader and

### Network Security Issues and Cryptography

Cryptography is the methods that allow information to be sent in a secure from in such a way that the only receiver able to retrieve this information. Presently continuous researches on the new cryptographic algorithms are going on. However, it is a very difficult to find out the specific algorithm, because we have already known that they must consider many factors like: security, the features of algorithm, the time complexity and

### A Novel Key Distribution Scheme f or a Visual Crypto System

network and internet, has hiked the chance of data snooped during the time of transmission. In this issue, Cryptography plays a vital role, which hides the actual information using some secret key and thereby converts it into an alternative equivalent multimedia file like image, video or audio in such a way that only the intended recipient can retrieve back the original data. Here in this paper, a novel secret sharing technique has been suggested, which comprises of two main parts. The first part for establishing shared secret key (one time key), using asymmetric key cryptography and then transmit the confidential data using that shared secret key, ensuring the confidentiality and integrity. Here for the encoding purpose Modulus Operation is used to increase the difficulty for the inverse function.