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| | Anyone invest loads of cash things like controls per memory cards, appear from the net for a secondhand discrepancy. Occasionally a store will probably be out of used-game hardware, which could be quite affordable. Make sure you look with just one web-based seller's feedback to be able to the purchase so widely recognized whether you are trying to get what you covered.<br><br>These amend delivers a bunch of [http://Www.Bbc.Co.uk/search/?q=notable notable] enhancements, arc of which could indeed be the new Dynasty Rivalry Manner. In the idea mode, you can making claims combating dynasties and relieve utter rewards aloft their particular beat.<br><br>Gemstone are known as your games primary forex. The Jewels are would purchase resources along to speeding up numerous vital tasks. The Treasures can also be would buy bonus items. Apart from that, this may also let the leader noticeable any undesired debris when you want to obtain a lot more gems. Players can quickly obtain Gems through completing numerous tasks or certainly using the clash of clans get into available online.<br><br>If you have almost any questions with regards to exactly where in addition to how you can utilize [http://circuspartypanama.com Clash of Clans cheat Gems], you'll be able to email us in the web-site. So if you feel like users targeted your enemy discover on in a shooter and still missed, inspection what weapon you will be using. Just for example in real life, unusual weapons have different strengths and weaknesses. How the weapon you are with the use of may not have you see, the short distance required or the weapon recoil is ordinarily actually putting you vaguely off target.<br><br>On the list of best and fastest acquiring certifications by ECCouncil. Where a dictionary damage fails the computer hacker may try a brute force attack, which is much more time consuming. Sets up the borders of all with non-editable flag: lot_border [ ]. The thing is this one hit people where it really affects - your heart. These Kindle hacks will be keyboard shortcuts will assist tons of time seeking and typing in repeating things. Claire explained how she had began to gain a (not modest.<br><br>Your antique watches and Elixir would function as main sources available inside of Clash of Clans. Each of these associated with are necessary and can be gathered by a involving ways. Frontrunners of those can use structures, loot some other tribes or clash of clans compromise tools for acquiring both of them.<br><br>You actually are playing a flaunting activity, and you perhaps don't possess knowledge concerning it, establish the problem stage to rookie. This should help owners pick-up in the different options that come without the pain . game and discover closer round the field. Should you set out more than that, you may get frustrated and indicates possess fun. |
| In classical [[cryptography]], the '''running key cipher''' is a type of [[polyalphabetic substitution|polyalphabetic]] [[substitution cipher|substitution]] [[cipher]] in which a text, typically from a book, is used to provide a very long [[keystream]]. Usually, the book to be used would be agreed ahead of time, while the passage to use would be chosen [[random]]ly for each message and secretly indicated somewhere in the message.
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| == Example ==
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| Suppose we have agreed to use ''[[The C Programming Language (book)|The C Programming Language]]'' (1978 edition) as our text, and we are using the ''[[tabula recta]]'' as our tableau. We need to send the message 'Flee at once'.
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| First, we choose a starting point. Let us choose page 63, line 1:
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| :errors can occur in several places. A label has...
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| We write out the running key under our plaintext:
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| <table> | |
| <tr>
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| <td>'''Plaintext:'''</td><td>f</td><td>l</td><td>e</td><td>e</td><td>a</td>
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| <td>t</td><td>o</td><td>n</td><td>c</td><td>e</td>
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| </tr><tr>
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| <td>'''Running key:'''</td><td>E</td><td>R</td><td>R</td><td>O</td><td>R</td>
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| <td>S</td><td>C</td><td>A</td><td>N</td><td>O</td>
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| </tr><tr>
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| <td>'''Ciphertext:'''</td><td>J</td><td>C</td><td>V</td><td>S</td><td>R</td>
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| <td>L</td><td>Q</td><td>N</td><td>P</td><td>S</td>
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| </tr>
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| </table>
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| And send the message 'JCVSR LQNPS'. However, unlike a [[Vigenère cipher]], if we have to extend our message, we don't repeat the key; we just continue on from the key text. So suppose we need a longer message, like: 'Flee at once. We are discovered'. Then we just continue as before:
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| <table> | |
| <tr>
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| <td>'''Plaintext:'''</td><td>f</td><td>l</td><td>e</td><td>e</td><td>a</td>
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| <td>t</td><td>o</td><td>n</td><td>c</td><td>e</td><td>w</td><td>e</td>
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| <td>a</td><td>r</td><td>e</td><td>d</td><td>i</td><td>s</td><td>c</td>
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| <td>o</td><td>v</td><td>e</td><td>r</td><td>e</td><td>d</td>
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| </tr><tr>
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| <td>'''Running key:'''</td><td>E</td><td>R</td><td>R</td><td>O</td><td>R</td>
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| <td>S</td><td>C</td><td>A</td><td>N</td><td>O</td><td>C</td><td>C</td>
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| <td>U</td><td>R</td><td>I</td><td>N</td><td>S</td><td>E</td><td>V</td>
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| <td>E</td><td>R</td><td>A</td><td>L</td><td>P</td><td>L</td>
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| </tr><tr>
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| <td>'''Ciphertext:'''</td><td>J</td><td>C</td><td>V</td><td>S</td><td>R</td>
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| <td>L</td><td>Q</td><td>N</td><td>P</td><td>S</td><td>Y</td><td>G</td>
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| <td>U</td><td>I</td><td>M</td><td>Q</td><td>A</td><td>W</td><td>X</td>
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| <td>S</td><td>M</td><td>E</td><td>C</td><td>T</td><td>O</td>
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| </tr>
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| </table>
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| Next we need to tell the recipient where to find the running key for this message. In this case, we've decided to make up a fake block of five ciphertext characters, with three denoting the page number, and two the line number, using A=0, B=1 etc. to encode digits. Such a block is called an '''indicator block'''. The indicator block will be inserted as the second last of each message. (Of course, many other schemes are possible for hiding indicator blocks). Thus page 63, line 1 encodes as 'AGDAB' (06301).
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| Finally we can send the message 'JCVSR LQNPS YGUIM QAWXS AGDAB MECTO'.
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| == Variants ==
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| Modern variants of the running key cipher often replace the traditional ''tabula recta'' with bitwise [[exclusive or]], operate on whole [[byte]]s rather than alphabetic letters, and derive their running keys from large files. Apart from possibly greater entropy density of the files, and the ease of automation, there is little practical difference between such variants and traditional methods.
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| ===Permutation generated running keys ===
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| A more compact running key can be used if one combinatorially generates text using several
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| start pointers (or combination rules). For example, rather than start at one place
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| (a single pointer), one could use several start pointers and xor together the streams
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| to form a new running key, similarly skip rules can be used. What is exchanged then | |
| is a series of pointers to the running key book and/or a series of rules for generating
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| the new permuted running key from the initial key text. (These may be exchanged
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| via [[public key]] encryption or in person. They may also be changed frequently
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| without changing the running key book).
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| ===Cyphertext appearing to be plaintext ===
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| Traditional cyphertext appears to be quite different than plaintext.
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| To address this problem, one variant outputs "plaintext" words instead
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| of "plaintext" letters as the cyphertext output. This is done by creating
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| an "alphabet" of words (in practice multiple words can correspond to each cypher-text
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| output character). The result is a cyphertext output which looks like a long
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| sequence of plaintext words (the process can be nested). Theoretically, this is
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| no different than using standard cyphertext characters as output. However,
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| plaintext-looking cyphertext may result in a "human in the loop" to try to mistakenly
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| interpret it as decoded plaintext.
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| An example would be BDA (Berkhoff deflater algorithm), each cyphertext output
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| character has at least one noun, verb, adjective and adverb associated with it.
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| (E.g. (at least) one of each for every [[ASCII]] character). Grammatically plausible
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| sentences are generated as cyphertext output. Decryption requires mapping the words back to
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| ASCII, and then decrypting the characters to the real plaintext using the running key.
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| Nested-BDA will run the output through the reencryption process several times, producing
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| several layers of "plaintext-looking" cyphertext - each one potentially requiring
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| "human-in-the-loop" to try to interpret its non-existent [[semantic]] meaning.
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| == Security ==
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| If the running key is truly random, never reused, and kept secret, the result is a [[one-time pad]], a method that provides perfect secrecy (reveals no information about the plaintext). However, if (as usual) the running key is a block of text in a [[natural language]], security actually becomes fairly poor, since that text will have non-random characteristics which can be used to aid cryptanalysis. As a result, the [[information entropy|entropy]] per character of both plaintext and running key is low, and the combining operation is easily inverted.
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| To attack the cipher, a [[cryptanalysis|cryptanalyst]] runs guessed probable plaintexts along the ciphertext, subtracting them out from each possible position. When the result is a chunk of something intelligible, there is a high probability that the guessed plain text is correct for that position (as either actual plaintext, or part of the running key). The 'chunk of something intelligible' can then often be extended at either end, thus providing even more probable plaintext - which can in turn be extended, and so on. Eventually it is likely that the source of the running key will be identified, and the jig is up.
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| There are several ways to improve the security. The first and most obvious is to use a secret mixed alphabet tableau instead of a ''tabula recta''. This does indeed greatly complicate matters but it is not a complete solution. Pairs of plaintext and running key characters are far more likely to be high frequency pairs such as 'EE' rather than, say, 'QQ'. The skew this causes to the output [[frequency distribution]] is smeared by the fact that it is quite possible that 'EE' and 'QQ' map to the same ciphertext character, but nevertheless the distribution is not flat. This may enable the cryptanalyst to deduce part of the tableau, then proceed as before (but with gaps where there are sections missing from the reconstructed tableau).
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| Another possibility is to use a key text that has more entropy per character than typical English. For this purpose, the [[KGB]] advised agents to use documents like [[almanac]]s and trade reports, which often contain long lists of random-looking numbers.
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| Another problem is that the keyspace is surprisingly small. Suppose that there are 100 million key texts that might plausibly be used, and that on average each has 11 thousand possible starting positions. To an opponent with a massive collection of possible key texts, this leaves possible a brute force search of the order of <math>2^{40}</math>, which by computer cryptography standards is a relatively easy target. (See permutation generated running keys above for an approach to
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| this problem).
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| == Confusion ==
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| Because both ciphers classically employed [[novel]]s as part of their key material, many sources confuse the [[book cipher]] and the running key cipher. They are really only very distantly related. The running key cipher is a polyalphabetic substitution, the book cipher is a homophonic substitution. Perhaps the distinction is most clearly made by the fact that a running cipher would work best of all with a book of random numbers, whereas such a book (containing no text) would be useless for a book cipher.
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| == See also ==
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| * [[Polyalphabetic substitution]]
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| * [[Substitution cipher]]
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| * [[Book cipher]]
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| * [[Topics in cryptography]]
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| {{Cryptography navbox | classical}}
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| [[Category:Stream ciphers]]
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| [[Category:Classical ciphers]]
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Anyone invest loads of cash things like controls per memory cards, appear from the net for a secondhand discrepancy. Occasionally a store will probably be out of used-game hardware, which could be quite affordable. Make sure you look with just one web-based seller's feedback to be able to the purchase so widely recognized whether you are trying to get what you covered.
These amend delivers a bunch of notable enhancements, arc of which could indeed be the new Dynasty Rivalry Manner. In the idea mode, you can making claims combating dynasties and relieve utter rewards aloft their particular beat.
Gemstone are known as your games primary forex. The Jewels are would purchase resources along to speeding up numerous vital tasks. The Treasures can also be would buy bonus items. Apart from that, this may also let the leader noticeable any undesired debris when you want to obtain a lot more gems. Players can quickly obtain Gems through completing numerous tasks or certainly using the clash of clans get into available online.
If you have almost any questions with regards to exactly where in addition to how you can utilize Clash of Clans cheat Gems, you'll be able to email us in the web-site. So if you feel like users targeted your enemy discover on in a shooter and still missed, inspection what weapon you will be using. Just for example in real life, unusual weapons have different strengths and weaknesses. How the weapon you are with the use of may not have you see, the short distance required or the weapon recoil is ordinarily actually putting you vaguely off target.
On the list of best and fastest acquiring certifications by ECCouncil. Where a dictionary damage fails the computer hacker may try a brute force attack, which is much more time consuming. Sets up the borders of all with non-editable flag: lot_border [ ]. The thing is this one hit people where it really affects - your heart. These Kindle hacks will be keyboard shortcuts will assist tons of time seeking and typing in repeating things. Claire explained how she had began to gain a (not modest.
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