According to searchsecurity.techtarget.com, “Encryption is the conversion of data into a form, called a ciphertext that cannot be easily understood by unauthorized people.” In order to understand the data or the message that is being sent, the receiver must be able to decrypt the message. Decryption thus refers to the process of converting the message from cipher text into its original format or plaintext whereby the reader would be able to understand the message. Encryption is used to ensure the confidentiality of a message that is being sent is not compromised as in case of the message being intercepted, it ensure that only authorized individuals are able to understand the contents. As technology has been advancing, the complex nature of encrypting and decrypting messages have also been advancing. Individuals and experts now create even harder to crack algorithms and formulae for encrypting data. Despite this, there are quite often ways in which a captured message can be decrypted without the use of brute force. The attack would be one that is based on cipher text only (www.londoninternational.ac.uk). This means that only the cipher text is acquired but has no knowledge of the meaning of the message in plaintext. One can try to critically and statistically analyze the cipher text, in order to try and derive the meaning of the encrypted text or look for combinations of common letters or character strings that would aid in the decrypting and understanding the captured message. Another such method, as stated as my peers, is to use the fact that symmetric encryption only uses a single secret key when encrypting a message. Thus, before capturing the message, the secret key can be covertly acquired through methods such as befriending an individual who has knowledge of the key or snooping to find the key. Thus once the encrypted message is obtained, the key will already be acquired so as to decipher the message. Another method of deciphering a captured message is...

...DATA ENCRYPTION AND DECRYPTION WITH ELLIPTIC CURVE CRYPTOGRAPHY
Ravi Kumar Kodali
Department of ECE National Institute of Technology Warangal,506004,INDIA
Abstract—Elliptic curve cryptography is the most popular cryptographic technique that provides higher security with a lesser key size.ECC Encryption and Decryption are implemented through Elliptic curve points operations like point addition,subtraction,doubling and scalar point multiplication.ECC cryptography technique is quite useful for WSN Applications.The security level increases with a larger keysize.The paper focuses on the implementation of ECC encryption and decryption with a key size of 163 bits.
proposed independently by Neal Koblitz and Victor Miller in 1985. They found the elliptic curve equation while for the arc length of an ellipse. Elliptic Curve is deﬁned by the following Weierstrass Equation: y 2 + (a1 xy) + a3 y = x3 + a2 x2 + a4 x + a6 (1)
Keywords: ECC,Encryption,Decryption,Key size I. INTRODUCTION Cryptography is the science and study of secret writing. The Cryptography means scrambling or modifying the information in such a way that it is not understandable and hence information is hidden from an unauthorized person. The main objectives of cryptography are Conﬁdentiality (the information cannot be understandable to anyone except to the intended person), Integrity (the information cannot be altered by third person between transmitter...

...substitution cipher in which each letter in the plaintext is shifted a certain number of places down the alphabet. For example, with a shift of 1, A would be replaced by B, B would become C, and so on (Lyons, 2009 - 2012). Caesar’s encryption method would be known as symmetric cryptography today.
Cryptography is considered not only a part of the branch of mathematics, but also a branch of computer science. There are two forms of cryptosystems: symmetric and asymmetric. Symmetric cryptosystems involve the use of a single key known as the secret key to encrypt and decrypt data or messages. When a message is sent, the user encrypts the message with a key which is known only to the intended recipient. The receiver will then use the known key to decrypt the message back into plaintext. The problem that symmetric cryptosystems have always faced is the lack of a secure means for the sharing of the secret key by the individuals who wish to secure their data or communications (Calloway, 2012). Additionally, the amount of keys needed for a large corporation could range into the millions, making symmetric encryption a poor choice. For example, if John, Jan, Bob, Bill, Margery, Maud, Wayne, Amber, Shane, and Phil all work together, they all need copies of each others’ encryption keys. Mathematically speaking, each individual would need 45 keys to be able to decrypt messages from all coworkers. Additionally, secret-key provides only limited...

...Date encryption is, in its simplest terms, the translation of data into a secret code. In order to read an encrypted file, the receiver of the file must obtain a secret key that will enable him to decrypt the file. A deeper look into cryptography, cryptanalysis, and the Data Encryption Standard (DES) will provide a better understanding of data encryption.
Cryptographic Methods There are two standard methods of cryptography, asymmetricencryption and symmetric encryption. Data that is in its original form (unscrambled) is called plaintext. Once the data is scrambled and in its encrypted form it is called cipher text. The cipher text, which should be unintelligible to anyone not holding the encryption key, is what is stored in the database or transmitted down the communication line.
Asymmetric encryption (also know as public key encryption) uses two separate keys, a public key and a private key. The private key is available only to the individual receiving the encrypted message. The public key is available to anyone who wishes to send data or communicate to the holder of the private key. Asymmetric encryption is considered very safe but is susceptible to private key theft or breaking of the private key (this is virtually impossible and would constitute trying billions of possible key combinations)
(4). Types of public key algorithms include...

...Image Encryption Using Block-Based Transformation Algorithm
Abstract:Encryption is mainly used to transmit the data over networks. There are so many techniques introduced which are used to protect the confidential image data from any unauthorized access. Multimedia data contains different types of data that includes text, audio, video, graphic,images with the increasing use of multimedia data over internet, here comes a demand of secure multimedia data. Most of the encryption algorithm available is generally used for text data and not suitable for multimedia data. In this paper we discuss a block based transformation algorithm in which image is divided in to number of blocks. These blocks are transformed before going through an encryption process. At the receiver side these blocks are retransformed in to their original position and performed a decryption process which gives the original image. Advantage of this approach, is that it reproduce the original image with no loss of information for the encryption and decryption process we used a blowfish algorithm.
KEYWORDS:Image Encryption, Image Correlation, Decryption, Image Entropy, Permutation.
INTRODUCTION
Encryption is a common technique to uphold image security in storage and transmission of digital images are exchanged over network types. The information security has become more important with the progress...

...ENCRYPTION
Introduction
Often there has been a need to protect information from 'prying eyes'. In the electronic age, information that could otherwise benefit or educate a group or individual can also be used against such groups or individuals. Industrial espionage among highly competitive businesses often requires that extensive security measures be put into place. And, those who wish to exercise their personal freedom, outside of the oppressive nature of governments, may also wish to encrypt certain information to avoid suffering the penalties of going against the wishes of those who attempt to control.
Still, the methods of data encryption and decryption are relatively straightforward, and easily mastered. I have been doing data encryption since my college days, when I used an encryption algorithm to store game programs and system information files on the university mini-computer, safe from 'prying eyes'. These were files that raised eyebrows amongst those who did not approve of such things, but were harmless [we were always careful NOT to run our games while people were trying to get work done on the machine]. I was occasionally asked what this "rather large file" contained, and I once demonstrated the program that accessed it, but you needed a password to get to 'certain files' nonetheless. And, some files needed a separate encryption program to decipher them.
Fortunately, my efforts back then...

...Network Security / e-Business Security
CAESER CIPHER – THE SHIFT CIPHER
1. Introduction
2. History & Development
3. How It Works
4. C++ Source Code [Encryption]
5. C++ Source Code [Decryption]
6. Step By Step Explanation [Decryption]
7. Step By Step Explanation [Decryption]
8. Pros & Cons
9. Conclusion
10. Reference
INTRODUCTION
In cryptography, a Caesar cipher, also known as Caesar's cipher, the shift cipher, Caesar's code or Caesar shift, is one of the simplest and most widely known encryption techniques. It is a type of substitution cipher in which each letter in the plaintext is replaced by a letter some fixed number of positions down the alphabet. For example, with a left shift of 3, D would be replaced by A, E would become B, and so on. The method is named after Julius Caesar, who used it in his private correspondence.
The encryption step performed by a Caesar cipher is often incorporated as part of more complex schemes, such as the Vigenère cipher, and still has modern application in the ROT13 system. As with all single alphabet substitution ciphers, the Caesar cipher is easily broken and in modern practice offers essentially no communication security.
HISTORY & DEVELOPMENT
The cipher was named after Julius Caesar. It was used during 50BC by notable Romans including Julius Caesar. In cryptography, the Caesar cipher is also known as Caesar’s shift or the...

...1
Encryption is method of scrambling data in some manner during transmission. In periods of war, the use of encryption becomes paramount so those messages are not intercepted by the opposing forces. There are a number of different ways to protect data during transmission, such as Substitution (character for character replacement) in which one unit (usually character) of cipher text (unintelligible text or signals produced through an encryption system) is substituted for a corresponding unit of plain text (the intelligible text or signals that can be read without using decryption), according to the algorithm in use and the specific key.
The other method is Transposition (rearrangement characters) which is the encryption process in which units of the original plain text (usually individual characteristics) are simply moved around; they appear unchanged in the cipher text for their relative location.
Study Case (Bank of Shenandoah Valley)
While both encryption and authentication method are providing some measures of security, the implementation of security itself has totally a different approach. Before any methods chosen, the two most important factors in security implementations are having to be determined. The level of security needed and the cost involved, so the appropriate steps can be taken to ensure a safe and secure environment. In this case Bank of Shenandoah Valley is in type of business...

...A preliminary version of this paper appears in the proceedings of Eurocrypt 2013. This is the full version.
Message-Locked Encryption and Secure Deduplication
Mihir Bellare1 Sriram Keelveedhi2 Thomas Ristenpart3
March 2013
Abstract We formalize a new cryptographic primitive, Message-Locked Encryption (MLE), where the key under which encryption and decryption are performed is itself derived from the message. MLE provides a way to achieve secure deduplication (space-eﬃcient secure outsourced storage), a goal currently targeted by numerous cloud-storage providers. We provide deﬁnitions both for privacy and for a form of integrity that we call tag consistency. Based on this foundation, we make both practical and theoretical contributions. On the practical side, we provide ROM security analyses of a natural family of MLE schemes that includes deployed schemes. On the theoretical side the challenge is standard model solutions, and we make connections with deterministic encryption, hash functions secure on correlated inputs and the sample-then-extract paradigm to deliver schemes under diﬀerent assumptions and for diﬀerent classes of message sources. Our work shows that MLE is a primitive of both practical and theoretical interest.
Department of Computer Science & Engineering, University of California San Diego, 9500 Gilman Drive, La Jolla, California 92093, USA. Email: mihir@eng.ucsd.edu. URL:...