Talk:Cipher

Categorizations

The last paragraph:

Most modern ciphers fall into three main categories: ... (followed by a list of four categories)

needs work.

I do not know for sure but suspect that: block vs stream and symmetric key vs asymmetric key are orthogonal categorizations. If that is the case, changing three to four (in the offending paragraph) does not really fix the problem. — Preceding unsigned comment added by Dairiki (talk • contribs) 00:13, 24 October 2002 (UTC)

Yep, they're orthogonal. I tidied up the last paragraph to reflect that. The rest of the article should probably be re-worked a bit for clarity as well. — Preceding unsigned comment added by Mbessey (talk • contribs) 30 January 2003 (UTC)

Merge request

Encryption and Cipher are currently too similar. They should be merged, or Cipher should be specialized to the customary (though vague) subset of private-key encryption. — Preceding unsigned comment added by Tromer (talk • contribs) 05:26, 22 February 2004 (UTC)

Disambiguation

While I'm a crypto-head and so probably biased, I do think there's a case for primary disambiguation here. I think any user typing in "cipher" is most likely to be looking for the encryption algorithm meaning, as opposed to a synonym for zero, or a Pokemon team of villains, or any of the other meanings. — Matt Crypto 11:33, 15 November 2006 (UTC)

Etymology

In hebrew/arabic "sifar" ספרה means "numerical digit". Thus, given the the fact that Hebrew culture has always had interest in such subjects as Numerology, the source of the word may have also come from that direction. Bilbobugginz (talk) 05:15, 14 July 2008 (UTC)

Merge with Encipherment

Encipherment does not contain enough information to stand on its own. It should be merged into this article.

Neelix (talk) 01:07, 6 May 2008 (UTC)

Huh? It's a redirect to this page. --84.250.188.136 (talk) 03:24, 9 May 2008 (UTC)

It wasn't when Neelix wrote the above. — Matt Crypto 05:22, 9 May 2008 (UTC)

 Done -- TNKS, Narnia.Gate7 (talk) 18:50, 4 May 2014 (UTC)

Another Type of Cipher

Hello, hope I'm doing this right, am new at it. Just writing to suggest something. Ciphers are often said to be either transposition, or substitution, or both; but there's also one appearing in Dorothy Sayers mystery novel, "The Nine Tailors," that, strictly speaking, is neither, for it embeds the plaintext message - without substitution, and without rearrangement - within a cover message (the key being a "change ringing" method for church bells). Can't stay to pursue this, but anyone's welcome to take it up. Boinkles (talk) 17:52, 24 August 2009 (UTC)

Steganography? — Matt Crypto 20:15, 24 August 2009 (UTC)

codes, ciphers, and telegraphy

The article describes "codes" in the cryptographic sense as operating on the level of meaning, e.g. words; versus "ciphers", which operate on the level of characters, groups of characters, or bits. It then gives telegraph code as an example of a code. But our article on telegraph codes points to Morse code, which operates on the level of characters, as the most common one. Is something meant by "telegraph code" here other than the kind that telegraph code describes? --Delirium (talk) 01:25, 5 September 2009 (UTC)

Yes, in this context a "telegraph code" is a book of codewords. Each codeword was typically 5 letters long and represented a longer word or short phrase, operating on the level of one or more full words.

The people who wrote the book "ABC Telegraphic Code" (and the people who wrote this "cipher" article) apparently think the term "telegraphic code" refers to that sort of codebook.

On the other hand, the people who set up our commercial code (communications) article and telegraph code article apparently think a "telegraph code" is a system that operates on the level of characters, representing each letter by a series of dots and dashes.

Please help us work out which one (or possibly both?) the Wikipedia "telegraph code" article should discuss at Talk:Telegraph code#Telegraph code vs Commercial code. --DavidCary (talk) 01:26, 27 March 2016 (UTC)

"Code" is indeed used in a variety of senses. "Telegraph code" can apply both to the practice of abbreviating or coding messages that are costed by word or by letter. One-for-one codes include Morse code, Baudot code and the International Telegraph Alphabet No2 (ITA2) which was a widely used 5-bit binary code in telegraphy and the even more widely used 7-bit American Standard Code for Information Interchange (ASCII) in computing. The purist cryptographic meaning of a cipher as opposed to a code relates to whether it is a simple one-to-one mapping between the characters (letters digits etc.) in the plaintext and the ciphertext. However, the verbs "decoding" and "deciphering" are in practice used interchangeably.--TedColes (talk) 13:33, 27 March 2016 (UTC)

The Telegraph code article needs a lot of attention.--TedColes (talk) 13:33, 27 March 2016 (UTC)

BMLFUVWØRKHAEIJAEST Indramorais (talk) 00:38, 12 January 2023 (UTC)

Example?

Under "Modern ciphers," it is written "Figure it out. 1554-275 0 13-64799 0-0". Assuming I have no background in cryptology and have come to Wikipedia out of curiosity on this subject, where would I begin in my work to solve what is apparently meant to be an example of a cipher? BlewJ (talk) 08:50, 21 August 2011 (UTC)

Current new News

Headline-1: Computer Engineer Cracks 150-Year-Old 'Odyssey' Code

• http://washingtonexaminer.com/computer-engineer-cracks-150-year-old-odyssey-code/video/gm-5274371

QUOTE: "For years, researchers have been trying to translate a series of mysterious notes in a copy of Homer's 'The Oyssey,' and someone finally did it." -- AstroU (talk) 15:19, 7 May 2014 (UTC) -- PS:FYI for future editing.

Headline-2: Mystery in centuries-old copy of 'Odyssey' solved

• http://technology.topnewstoday.org/technology/article/13479213/

QUOTE: "The University of Chicago says a computer engineer from Italy has solved a mystery found in a rare edition of Homer's "Odyssey" in the university library" -- AstroU (talk) 15:55, 7 May 2014 (UTC) -- PS:FYI for future editing.

Not a likely addition to this article. It turns out that these were shorthand notes in French dealing with translating Homer's greek. No secret, no mystery and definitely not a cipher. Bill Cherowitzo (talk) 05:42, 8 May 2014 (UTC)

Agreed. It was very interesting to me that they used Google-search as one of the tools to break what they thought was a cipher. So it was more of a code than a cypher. AstroU (talk) 13:33, 8 May 2014 (UTC)

You mentioned only 1 letter by 1 letter cipher but a good randomized cipher ciphers a huge list of English phrases with code numbers (which are only code numbers and have absolutely nothing to do with the size of the phrase) - the mechanism of selecting their labeling also has to be changeable - it works well ONLY if we combine that method with others

And we generate 1 initial list of minimum size of constant digits. Then we copy that list and create 20 more lists which have larger size of digits (the list two has labels which are one more digital longer than list 1, list 3 has labels which are one digit longer than list 2 etc)

Remember. Your list must be random "Uranus is my favorite planet." could be labeled as "0" and "#" could be labeled as "1". Labeling mustn't follow any logical order.

Then sometimes we introduce noise of certain digital length.

So the key could be:

34, 24, 68, 45, 13, 42 (with 68 and 42 as random insertions which have length 68 digits and 42 digits.)

34, 24, 68, 45, 13, 42 means select the labeling from the list 34 then from the list 24, add random noise for 68 digits etc.

But I didn't mention you how to "compress read" the initial text in order it fits your lists.

That method generates insanely huge files - but some prefer it.

You have to combine it with other cipher methods and make a system for list shuffling. — Preceding unsigned comment added by 2A02:2149:8464:BA00:BCE5:B794:8895:1FC4 (talk) 15:12, 15 February 2018 (UTC)

variant size of atlernative labeling + noise at some labeling series

• 1 meaning (letter of phrase) = 20 alternative ciphers of different size

  and 3 noise entries of different size

  20 and 3 is relative, you mustn't be strict with that because that would be a hint

• then you give a code so the person who reads your message knows the series of the variant sized lists, because each fragment of information corresponds to a different sized list in order we decipher it (also some series of data are pure noise, and we know their size because we have the key

• • I didn't tell how we compress the initial information in order it fits on our fragmentational system (cue other lists do the job/list labeling must shufflable if needed/that system works fine only if you combine it with other ciphering methods). — Preceding unsigned comment added by 2A02:2149:8464:BA00:BCE5:B794:8895:1FC4 (talk) 15:25, 15 February 2018 (UTC)

War cipher with phrase cipher

War cipher has basic phrases and topography. Time codes and basic actions.

for example the military E-mail: "&+d" could be phrase deciphered as a huge text

• ".. in the past also was tried to use sending time itself (seconds, because one cannot waste an hour) but it's usually (it depends on the system) considered unsafe "

• Also you might have the ability to send the information from many "towers" and the receiver might have the ability to understand which one was used. That alone is an information. - that is also unsafe if your correct tower is compromised (physical cipher is prone to physical or systemic error, usually at a higher rate than other code errors) — Preceding unsigned comment added by 2A02:2149:8464:BA00:BCE5:B794:8895:1FC4 (talk) 15:38, 15 February 2018 (UTC)

In the section Types/Modern, we have symmetric key algorithms (Private-key cryptography). It looks like the links on those have gotten disambiguated or w/e to now point to the same page. Seems kinda dumb to me to have two links to the page right next to each other. Also looks like the next line has the same issue. 2600:6C55:7D00:AE4:908E:FAA4:BF3E:3601 (talk) 23:36, 10 December 2021 (UTC)

Wiki Education assignment: Introduction to Information Studies

This article was the subject of a Wiki Education Foundation-supported course assignment, between 17 January 2023 and 11 March 2023. Further details are available on the course page. Student editor(s): Burkheadz (article contribs).

— Assignment last updated by LesserGoldfinch (talk) 22:32, 16 February 2023 (UTC)