Talk:Encryption

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 To-do list for Encryption: Revamp taxonomy diagram Illustrate general process of both public and private-key encryption. I believe that the first three words regarding cryptography have it backwards. Cryptographic protocols are a subset of encryption, not the other way around. Where, before computers, the distinction wasn't instructive, it is now. When I was provided the hyperbolic phrase, cryptographic encryption, it had a dissonance, because it was in the past redundant, and today, plain wrong. Encryption is the larger matter, various cryptographic schemes are a subset. But to simply re-write that, In encryption, cryptography etc etc does a huge injustice to clarity. Perhaps, Cryptography is a manner of encryption which employs an express protocol intended to... Maybe there can be a phrase to modify protocol, so we don't encrypt this revised definition. But this needs a discerning eye because physics and computer geeks are misusing this term by the second. ----

articles should be merged, too similar

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.

disagree, and problems w/ diagram

Tromer, Your observation is a common misunderstanding. Encryption can be done in several ways, only one of which uses a cypher. As for 'cipher' being customarily a subset of private-key encryption, that is true only if by private key one means symmetric key cypher. At least that's the sense I take from your comment. The spelling is (cy v ci) is irrelevant as to meaning, but excites comment (see Talk:Cryptography for some history on WP). As the diagram notes, cyphers come in symmetric and asymmetric flavors, and symmetric cyphers are sometimes (confusingly) called private key cyphers. Asymmetric key cyphers are sometimes (wrongly) taken to be all public key/private key cyphers. Not all are, as there exist some in which there are no public keys.

As for the diagram, I will note that the placement of rotor machine is probably incorrect. Rotor machines (as the Hebern machine, Enigma machine, SIGABA, Typex, and even the non-rotor Japanese stepping switch machines) are fundamentally substitution cyphers, albeit polyalphabetic ones. The diagram should reflect this. ww 15:12, 19 Jul 2004 (UTC)

I'm going to make a text version of the diagram here, so it's easier for me (and presumably others) to edit:

• Ciphers
• Classical
• Substitution
• Rotor machines
• Transposition
• Modern
• Public Key (shouldn't this be "assymetric key" ?)
• Private Key (shouldn't this be "symmetric key" ?)
• Stream
• Block

Do "Stream" and "Block" really only apply to "Private Key" ciphers ?

Steam and block: in usage, yes. "Public key" and "private key" are, essentially, synonymous with "assymetric" and "symmetric key".— Matt 09:18, 22 Aug 2004 (UTC)

Taxonomy approach

See also Image talk:Cipher-taxonomy.png. There is a problem with making a taxonomy of ciphers. There are (at least) two ways of approaching it, and each is somewhat unsatisfactory. The first is a more "abstract" classification, dividing the ciphers strictly according to how they function. The problem with this approach is that you then make distinctions that are never made in practice: the distinction between substitution and transposition is only really used in the context of classical ciphers; the distinction between symmetric and asymmetric ciphers is only really used in the context of modern cryptography, and so on.

The alternative approach, employed here, is to divide ciphers into sections according to how they are divided in practice. The problem with the "usage-reflecting" style is that, e.g., a classical substitution cipher isn't labelled as a symmetric key cipher, which might be desirable, but I think it's more important to reflect usage. — Matt 09:18, 22 Aug 2004 (UTC)

I think that classical ciphers would fit well enough under symmetric encryption in a symmetric vs. asymmetric layout. Jobarts-Talk 07:46, 19 January 2006 (UTC)

Encryption: hash functions?

I moved this recent addition here temporarily:

Cryptographic hashes, also known as one-way hashes or message digests, are used to encrypt data so that it cannot ever be decrypted, but it can be recognized because the same data always produces the same output. Other unique features of this form of encryption include that no matter the size of the input, the size of the output is always the same (the size of the output varies from algorithm to algorithm), and that no keys are used. Popular algorithms include MD5 and SHA. See the Cryptographic hash function entry for more information.

I'm not sure this is the right place to diversify into a discussion of crypto hash functions -- secure hashing isn't usually described as "encryption", although it's certainly part of cryptography and symmetric key cryptography. — Matt 13:14, 2 Oct 2004 (UTC)

I think this should be moved to the "Message verification" subsection. Greatpopcorn (talk) 03:02, 13 November 2013 (UTC)

Cryptographic hash functions

While cryptographic hash functions are certainly not a cipher, they are a vital part of encryption technology. Someone unfamiliar with the plumbing of encryption will just type "encryption" into Wikipedia and hope to get an overview of the subject with links to the details. This seems like a reasonable approach to making the Encryption and Cipher entries different so they work best for users. Encryption is a more general term.

It is logical that the Encryption entry should have brief descriptions of symmetric and asymmetric ciphers, hash functions and encryption-strength pRNGs in order to best serve users who may be unfamiliar with the categories or taxonomy related to the subject.

Vancegloster 21:27, 3 Oct 2004 (UTC)

OK, I can see what you're getting at here; you're saying that "encryption" is sometimes used to mean "encryption technology", which is essentially the field of "cryptography". Currently, we have an overview of the field in Cryptography, which deals (hopefully) with everything, including the entire gamut of PRNGs, digital signatures, hash functions, secret sharing schemes, authentication protocols, MACs and so on. This article, which deals with ciphers, is termed Encryption — in my experience, most cryptographers use "encryption" to refer to the action of ciphers, so it's a good title. You've pointed out, though, that sometimes people are looking for an overview of the entire field when they search for "encryption". Your suggestion is to move the cipher stuff into an article called Cipher, and have Encryption survey all the cryptography mechanisms. The problem with this is that most of Cryptography and Encryption would then be duplicating each other to a large extent. I'd propose an alternative: to this page, add a "disambiguation" header saying something like:
This article is about algorithms for encryption and decryption. For an overview of cryptographic technology related to encryption, see cryptography.
Do you think that would suffice? — Matt 22:14, 3 Oct 2004 (UTC)

This does seem reasonable. Vancegloster 23:54, 7 Oct 2004 (UTC)

Text added by anon user

This text was added by an anonymous user. I'm not at all sure what it is supposed to be saying, so I've moved it here:

practical example of not too deciphered news

--Fastfission 02:18, 27 Jan 2005 (UTC)

Fastfission, you did the first half of the job. I did the other half: I deleted all that gibberish by some German joker, who can't even write decent English. Just in case anyone wants to look at it, it's down there in this page's history. --AVM (talk) 16:08, 26 September 2008 (UTC)

Ciphers versus codes

Besides of a bit confusing diagram in the "Types of cipher" section, I think that in the "Ciphers versus codes" section distingushing between codes and ciphers based on amount of data processed (words x letters) is a misunderstanding.

As I always understood it, codes are not directly related with security (meaning security against intruders, etc.), but rather they are used to transfer data in a defined form and/or to secure data against transfer errors. For example [error correcting codes like the Hamming code or ASCII code and many others.

Therefore i disagree with the sentence: "Some systems used both codes and ciphers in one system, using superencipherment to increase the security."

Of course I mean the "technical discussions" usage of the words.

Finally, I found out that in cryptography article the definition of code x cipher is the same. But I still disagree :).

What are your opinions?

PeP

I agree that the diagram is confusing, so I've removed it for now. Codes were indeed used in cryptography for secrecy, and not (well, not primarily) for error checking or as a standard like ASCII. — Matt Crypto 21:05, 14 January 2006 (UTC)

Encryption (album)

I apologise, I don't know how to use the coding that has been used at the top of the article to talk about other uses of the word. I just thought that it may be worth adding a note about the album Encryption by Pro-jekt. J Milburn 16:29, 11 September 2006 (UTC)

Anyone? J Milburn 09:46, 22 October 2006 (UTC)