Simple ciphers are both easy to encrypt and decrypt, the only problem with this is that they are also easy so crack. The two main simple ciphers are explained below:.
A Transposition Cipher is a cipher where no letters in the message are changed around but simply positioned in a different order, for example THIS IS AN EXAMPLE could be encrypted as SIHT SI NA ELPMAXE. This cipher is simple to recognize and decode as the letters in each word are simply reversed.
A Substitution Cipher is a process where the orders of the letters are not changed but simply their identity. For example, using the table below the word DOG can be encoded as JUM. We do this by finding the first letter in the original message (plaintext) in the top row of the table and then replacing it with the letter directly below it in the table (ciphertext).
The main problem with these two types of cipher is that they can be easily cracked. This is because the ciphertext they produce contains the same frequency of letters as the plaintext. Through a process called frequency analysis, given a sufficiently large ciphertext it can easily be cracked by mapping the frequency of its letters to the known frequency of, for example, English text.
Polyalphabetic Cipher.
Because of the problems caused by the above ciphers a new type of cipher was needed. A Polyalphabetic cipher involves the use of more than one cipher alphabet. Therefore each letter would have a one to many relationship with its substitute as oppose to a one to one.
The Vigenere Cipher was devised by Blaise de Vigenere from the court of Henry III of France in the sixteenth century. This polyalphabetic cipher is based on the following tableau. As you can see on the table the first row ia a shift of 0, the second is a shift of 1, the last is a shift of 25.
Method: If we wanted to encipher the plaintext ANNA LIKES BANANAS using the Vigenere cipher we would first have to choose a key word, we will use MEDIA.
It is a kind of block cipher. ... Security of data is excellent with this cipher. ... It is fast stream cipher. ... With the help of these cipher's algorithms one can generates its own cipher text algorithms by making modification into existing cipher text algorithms. Also performance evaluation of various ciphers can be done with the help of the cipher's algorithms discussed in this paper....
There are a number of different ways to protect data during transformation, such as substitution, character for character replacement, the spartan scytale, transposition ciphering, rail-fence ciphering, paper and pen ciphering, and finally the most recent algorithmic encryption. ... Once the data is scrambled and in its encrypted form it is called cipher text. ... There are seven basic types of attack: cipher text-only, known-plaintext, chosen-plaintext, adaptive chosen-plaintext, chosen-cipher text, man-in-the-middle, and brute force. ... Cipher text-only attack is the result of an attacke...
These public executions are designed to prevent similar acts of dissention among the ciphers. Ciphers understand that their lives are the property of One State's, meaning they exist just by the government's will. ... Since ciphers are subjected to the Table of Hours, nearly all parts of the day are regulated by the State, with the exception of the two personal hours. ... D-503 and the rest of the ciphers are led to believe that the restriction of liberty is necessary to protect the State. ... In One State, ciphers can have conflicting emotions, as D-503 frequently exhibits in his wri...
Cipher Method or Symbolic Dream Interpretation In chapter two of Interpretation of Dreams, there are two methods discussed to extract the meanings of dreams and how they correlate to ones life. ... The second theory is the Cipher Method, which is explained though an elaborate key of explanations. ... The cipher method seems to be the most accurate for interpretation. ... So, now I will try to use the cipher method to analyze this dream. ... Now that I have use the cipher method to analyze it I will incorporate it to why it is a reoccurring dream. ...
Cipher Method or Symbolic Dream Interpretation In chapter two of Interpretation of Dreams, there are two methods discussed to extract the meanings of dreams and how they correlate to ones life. ... The second theory is the Cipher Method, which is explained though an elaborate key of explanations. ... The cipher method seems to be the most accurate for interpretation. ... So, now I will try to use the cipher method to analyze this dream. ... Now that I have use the cipher method to analyze it I will incorporate it to why it is a reoccurring dream. ...
This is achieved by communicating messages between the two machines to determine which "cryptographic algorithm" or "cipher" to use to encrypt the data. ... Clients and servers may support different cipher suites, or sets of ciphers, depending on factors such as the version of SSL they support, company policies regarding acceptable encryption strength, and government restrictions on export of SSL-enabled software. Among its other functions, the SSL handshake protocol determines how the server and client negotiate which cipher suites they will use to authenticate each other, to transmit certifi...
Clients and servers may support different cipher suites, or sets of ciphers, depending on factors such as the version of SSL they support, company policies regarding acceptable encryption strength, and government restrictions on export of SSL-enabled software. Among its other functions, the SSL handshake protocol determines how the server and client negotiate which cipher suites they will use to authenticate each other, to transmit certificates, and to establish session keys. The cipher suite descriptions that follow refer to these algorithms [1]: DES. ... Rivest encryption ciphe...
Security on the Web, By Sina How do you secure something that is changing faster than you can fix it? The Internet has had security problems since it's earliest days as a pure research project. Today, after several years and orders of magnitude of growth, it still has security problems. The Internet is being used for a purpose for which it had never intended to be used for. It is somewhat ironic that the early Internet was design as a prototype for a high-availability command and control network that could resist outages resulting from an enemy attack, yet it cannot resist college unde...
Enigma, to historians, is a German mechanical ciphering machine. ... Even Thomas Jefferson had invented a ciphering machine consisting of numerous rings on the same shaft, which is similar to the design of Enigma. ... When figuring out the ciphered letter, Enigma would have to go through each rotor in order to get the new coded letter. ... When all the coding was done, the cipher would be unbreakable. ...