Talk:Encryption

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	To-do list for Encryption:	edit  · history  · watch  · refresh
Revamp taxonomy diagram Illustrate general process of both public and private-key encryption.

Contents 1 articles should be merged, too similar 2 disagree, and problems w/ diagram 3 Taxonomy approach 4 Encryption: hash functions? 5 Cryptographic hash functions 6 Text added by anon user 7 Ciphers versus codes 8 Encryption (album) 9 External links 10 where's sourcecode?

[edit] 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.

[edit] 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)

[edit] 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)

[edit] 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)

[edit] 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)

[edit] 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

Transmitters and receivers unite on it, e.g., the Internet page:

http: // de.wikipedia.org/wiki/Verschlüsselung

the key is, now the transmitter wants to send the news (Hallo mir gehts gut)

because here on this side the first letter H is found several times, he can choose practically any Kordinantenangabe for this, e.g. (line 1, place 6) H from the Title or the information (line 10, place 11) what H from the word to cryptographers corresponds. As long as transmitters and receivers do not frequent the side excessively as a key and know only them the Domain, it is to be gone for outsiders undependent on every computing capacity impossibly conclusions to this side and to decode something.

Alternatively every any letter lettuce can be also used, vorraus sedately him only transmitters and receivers use, it can be of course also every any Perry Rhodam Booklet or an issue of a very rare issue of any thick book. However, thanks today's Speicherkapizitäten it can be per letter also a whole book if about one DVD is filled with nothing to other than text file.

With only 2 same books and a mobile with SMS function is, every radio pair can switch off so already potential listeners completely what has made oddly enough many of the millions and billions expensive bugging systems in the world of the Secret Services, nevertheless, barely superfluous.

El Qaeda uses rare issues of Arabian poets, Mafiosis maybe only the recipes of mum. All listening specialists might despair, in any case, of it, because software cannot function for deciphering of files if none to encodes it was used and, instead, only the keys.

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

[edit] 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)

[edit] 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)

[edit] External links

I'm restoring edits to the External links section that were reverted by User:Austinmurphy, claiming they were self promotion. I have nothing to do with any of the sites listed before or after the edits. Some of the changes I made were to conform to Wikipedia capitalization style. I removed three links, one to an article that promoted several commercial products for tape backup, one to Encryption, from MysecureCyberspace's encyclopedia on cybersecurity which has a couple of paragraphis on the subject and a link back to Wikipedia, and SecurityBulletins.com Basic Encryption testing methods, which suggest users test encryption software by trying to compress the output, a rather inadequate approach, to say the least. I also replaced a link to the pgpi website which is rather out of date with one to the GPG website. If anyone has a problem with these changes please discuss it here. --agr 22:30, 18 October 2006 (UTC)

[edit] where's sourcecode?

i'm not a mathetician, hell i failed all my math classes, but i consider myself to be a programmer but i've learn some math just by programing.. (weird huh?) is there any non math equations that show encryption techniques, the links like this [1] didn't help much, i rather have newbie friendly sourcecode.. to examine and apply. —The preceding unsigned comment was added by 75.15.191.81 (talk) 02:31, 4 January 2007 (UTC).