Data Encryption Essays - Cryptography, Symmetric-key Algorithm

Data Encryption Essays - Cryptography, Symmetric-key Algorithm Data Encryption The electronic age has brought forth many technological advances. With these advances came the need for security and tighter control on how we send information electronically over the Internet or through a network. 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 date encryption. Cryptographic Methods There are two standard methods of cryptography, asymmetric encryption 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 ciphertext. The ciphertext, 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 Riverst-Shamir-Adelman (RSA), Diffie-Hellman, Digital Signature Standard (DSS), EIGamal, and LUC (5). Symmetric encryption uses only one key (a secret key) to encrypt and decrypt the message. No public exchange of the key is required. This method is vulnerable if the key is stolen or if the ciphertext is broken (4). Types of symmetric algorithms include DES, Blowfish, International Data Encryption Algorithm (IDEA), RC4, SAFER, and Enigma (5). Cryptanalysis Cryptanalysis is the art of breaking cryptography. Methods of cryptanalysis include: h Ciphertext-only attack V the attacker works from ciphertext only. The attacker does not know anything about the message and is merely guessing about the plaintext (6). h Know-plaintext attack V the attacker know the plaintext. Knowing this information, the attacker can attempt to decrypt the ciphertext (6). h Chosen plaintext attack V the attacker can have a message encrypted with the unknown key. The attacker must then determine the key used for encryption (6). h Man-in-the-middle attack V the attacker intercepts the key that is being exchanged between parties (6). Data Encryption Standard (DES) In 1977 the National Institute of Standards and Technology (NIST) and IBM developed the Data Encryption Standard, or DES, to provide a means by which data could be scrambled, sent electronically to a destination, and then unscrambled by the receiver. DES was developed to protect data in the federal computer systems against passive and active attacks (3). Every five years the NIST reviews the DES and determines whether the cryptographic algorithm should be revised, is acceptable, or completely withdrawn. DES uses a very complex algorithm, or key, that has been deemed unbreakable by the U.S. government. There are 72,000,000,000,000,000 (72 quadrillion) or more possible encryption keys that can be used. It applies a 56-bit key to each 64-bit block of data. This process involves 16 rounds of operations that mix the data and key together using operations of permutation and substitution. The end result is a completely scrambled data and key so that every bit of the ciphertext depends on every bit of the data plus every bit of the key (a 56-bit quantity for DES) (2). Conclusion Sending secure electronic information is vital for businesses today. Although the electronic age has made it easier for companies to send and receive information, it has also increased the need for security. Data encryption in itself will not assure any business of sending secure information, but understanding it will surely benefit the company. Businesses who understand cryptography, cryptanalysis, and Data Encryption Standard are on their way to understanding data encryption. Bibliography 1. Bay Networks, Inc. (1997). Configuring Software Encryption. www.baynetworks.com 2. Biasci, L. (1999). Cryptology. www.whatis.com. 3. Frazier, R.E., (1999). Data Encryption Techniques. www.softstrategies.com. 4. Litterio, F., (1999). Cryptology: The Study of Encryption. www.world.std.com. 5. SSH Communications Security, (1999). Cryptographic Algorithms. www.ipsec.com. 6. SSH Communications Security, (1999). Introduction

Jane Austens Complete List of Famous Works

Jane Austens Complete List of Famous Works Jane Austen is recognized as one of the most important English writers of her time. Shes probably most famous for her novel  Pride and Prejudice, but others like  Mansfield Park, are very popular. Her books largely dealt with themes of love and a womans role in the home. While many readers try to relegate Austen to the realms of early chick lit, her books are important to the literary canon. Austen is one of the most important British authors.   While today her novels are often considered by some to be part of the romance genre, Austens books actually helped popularize the idea of marrying for love in the first place. During Austens time marriage was more of a business contract, couples would decide to get married based on things like each others economic class. As one can imagine marriages like this werent always the best for women. Marriages built on love rather than for business reasons were a common plot point in many of Austens novels. Austens novels also pointed out the many ways women of her time depended on their ability to marry well.   Women rarely worked during Austens job and the few jobs they did hold were often service positions like cook or governess. Women relied on their husbands employment to provide for any family they might have.   Austen was a trailblazer in multiple ways, she chose not to marry and managed to earn money with her writing. While many artists arent appreciated in their lifetime, Austen was a popular author within her own life. Her books afforded her the ability not to need a husband to rely on. Her list of works is rather short by comparison but this is most likely due to her life being cut short due to an unknown illness. Jane Austens   Works Novels 1811 - Sense and Sensibility1813 - Pride and Prejudice1814 - Mansfield Park1815 - Emma1818 - Northanger Abbey (posthumous)1818 - Persuasion (posthumous) Short fiction 1794, 1805 - Lady Susan Unfinished fiction 1804 - The Watsons1817 - Sanditon Other works 1793, 1800 - Sir Charles Grandison1815 - Plan of a NovelPoemsPrayersLetters Juvenilia - Volume the First The Juvenilia is comprised of several notebooks Jane Austen wrote during her youth.   Frederic ElfridaJack AliceEdgar EmmaHenry and ElizaThe Adventures of Mr. HarleySir William MountagueMemoirs of Mr. CliffordThe Beautifull CassandraAmelia WebsterThe VisitThe MysteryThe Three SistersA beautiful descriptionThe generous CurateOde to Pity Juvenilia - Volume the Second Love and FriendshipLesley CastleThe History of EnglandA Collection of LettersThe female philosopherThe first Act of a ComedyA Letter from a Young LadyA Tour through WalesA Tale Juvenilia - Volume the Third EvelynCatharine, or the Bower