Talk:Encryption

From Wikipedia, the free encyclopedia

WikiProject on Cryptography This article is part of WikiProject Cryptography, an attempt to build a comprehensive and detailed guide to cryptography on Wikipedia. If you would like to participate, you can choose to edit the article attached to this page, or visit the project page, where you can join the project and see a list of open tasks.
WikiReader Cryptography It is intended that this article be included in WikiReader Cryptography, a WikiReader on the topic of cryptography. Help and comments for improving this article would be especially welcome. A tool for coordinating the editing and review of these articles is the daily article box.
To-do list for Encryption: edit · history · watch · refresh
  • Revamp taxonomy diagram
  • Illustrate general process of both public and private-key encryption.

Contents

[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).

Try [2]--agr 02:19, 5 June 2007 (UTC)

[edit] Trim see also

I trimmed the see also section. I think it should be kept to major topics in encryption, and not become a laundry list of articles that touch on encryption. In particular I removed the recently added Zodiac Killer link, but I did add the the unsolved codes and ciphers category to the Zodiac Killer article. --agr 02:19, 5 June 2007 (UTC)

[edit] History of the word 'cipher'

To quote pages 80-81 of Zero, The Biography of a Dangerous Idea, by Charles Seife:

Italian merchants loved the Arabic numbers. They allowed the bankers to get rid of their counting boards. However, while businessmen saw their usefulness, the local governments hated them. In 1299, Florence banned Arabic numerals. The ostensible reason was that the numbers were easily changed and falsified. (A 0 could be turned into a 6 with a simple flourish of a pen, for instance.) But the advantages of zero and other Arabic numerals were not so easily dispensed with; Italian merchants continued to use them, and even used them to send encrypted messages - which is how the word 'cipher' came to mean "secret code."

Of course, you must keep in mind that Zero-into-6 was at the core of the issue, and that the old name for Zero was cipher.

ryanakca 14:57, 31 August 2007 (UTC)

[edit] Spliting this article

Most of this article is about term "cipher", not about term "encryption". I see that this article was created by merger of those two articles, so this situation is understandable. I propose 2 possible solutions:

  1. move this article to Cipher
  2. split this article to Cipher and Encryption by moving everything except the introduction to Cipher and leaving only the intro section here. That would make Encryption a stub, but would solve our problem. --Dijxtra (talk) 21:31, 27 November 2007 (UTC)
I would suggest we move out the Etymology of cipher section only. A cipher is an algorithm for encryption — essentially, it's the same topic. — Matt Crypto 22:13, 27 November 2007 (UTC)
Yes, it's the same topic, but two different terms. It's a bit confusing this way: article which is about cipher is named "encryption". I think we gain a lot on clarity if we move the stuff about the cipher to new article called "Cipher". I don't see why we can't have a small article "Encryption" which would say something like "encryption is the act of using a cipher", and then a big "Cipher" article which deals with term cipher. Wouldn't that be terminologically correct? --Dijxtra (talk) 08:41, 28 November 2007 (UTC)
As there were no stern opposes, I proceeded with split. Now I will revamp the articles to make 2 meaningful entities. --Dijxtra (talk) 11:45, 29 November 2007 (UTC)
Hmmm. I agree that this article could do with cleaning up, but I don't think two separate articles on the same topic is the best way to go. After all, how do you decide what goes in cipher and what goes in encryption if they're covering the same thing? I suggest we merge them back; I don't particularly mind if the article is called "cipher" or "encryption", but I think we should really cover it in one place. — Matt Crypto 20:38, 29 November 2007 (UTC)
In most current usage, I believe, "encryption" is a broader term than "cipher" and includes techniques such as code books and secret algorithms that do not have a key. Arguably it could extend to analog scramblers and mechanical devices. So I think the split is a good idea, but the encryption article needs to written more broadly. It should mention classical ciphers, rotor machines, codes, and give a brief intro to public key crypto. --agr (talk) 21:28, 29 November 2007 (UTC)

[edit] References

Two of the five references were to obscure papers by a Saudi. I removed them. Care should be taken to make sure he doesn't add them back. The references should be to well known authoritative works like _Code Breakers_. —Preceding unsigned comment added by 67.163.141.50 (talk) 13:23, 26 April 2008 (UTC)

Why would an obscure work not be appropriate? I haven't seen that in any guidelines. Binksternet (talk) 13:32, 26 April 2008 (UTC)

[edit] Ibrahim Al-kadi references

Somebody keeps removing the works by Ibrahim Al-kadi. Please explain why. Binksternet (talk) 13:30, 26 April 2008 (UTC)

Would you mind explaining why you think these references should be in the article. 85.2.112.20 (talk) 15:17, 26 April 2008 (UTC)
I haven't read them; I have no idea what's in them. I am simply reacting to their removal without sufficient explanation. Their being obscure isn't good enough reason for removal. Binksternet (talk) 16:29, 26 April 2008 (UTC)
Ok, thanks for the clarification. 85.2.112.20 (talk) 17:11, 26 April 2008 (UTC)
I think it's fair to ask why they are present in this article. They do look like random citations -- why not any of the other hundreds of journal and conference papers about crypto? Are they being used as a source for any specific point in this article? There's certainly nothing in this article specifically about Arabic cryptology. We have more specialised articles (e.g. History of cryptography). — Matt Crypto 17:12, 26 April 2008 (UTC)
Good points. Binksternet (talk) 15:12, 28 April 2008 (UTC)