There's a useful table containing both measurements for all the RSA numbers (old and new) here.
RSA-200 is 663 bits long. It's interesting to contrast it with RSA-640 (640 bits long). RSA-640 is shorter, so should be easier to factor. And unlike RSA-200, RSA-640 carries a cash prize of US$20,000 for its factorisation. So, a puzzling question is why did the team take on RSA-200 rather than RSA-640?
Basic Enigma-style algorithms ("rotor machines with reflectors") seem to have fundamental weaknesses. Two that spring to mind are: 1) The rotors step regularly; and 2) A plaintext letter can never encrypt to itself.
A virtual Enigma machine with thousands of rotors (etc) might be secure enough in actual practice, but would be a lot slower than current algorithms (even slower than, say, Triple DES). The Enigma was quite weak, though, compared to later machines: check out systems like SIGABA (US), KL-7 (NATO) or HX-63 (commercial) for some very secure rotor devices.
Regarding Enigma and the Allies...you're close: at the end of 1932, a Polish mathematician named Marian Rejewski deduced the Enigma rotor wirings using a combination of operator error, procedural flaws (the double indicator thing you mentioned), a key settings list obtained from a German cipher-clerk-turned-traitor (the spying), inspiration -- and a large dose of mathematical genius.
See: Marian Rejewski on Wikipedia
You can find collisions for SHA-0 faster than expected, and it's claimed that you can do the same for SHA-1 (the attack hasn't yet been published, but it's pretty certain to be genuine). The SHA-2 algorithms (that is, any of SHA-224, SHA-256, SHA-384, or SHA-512) remain uncompromised. See: SHA article on Wikipedia.
Elliptic curve cryptography is (if you squint your eyes) a translation of older crypto techniques onto slightly more exotic mathematical objects. Rather than (say) integers modulo a prime, ECC uses a group of an elliptic curve over some finite field. But the new techniques are analogous to the old: Diffie-Hellman, ElGamal, DSA. The advantage is meant to be that keys can be a lot smaller for an equivalent level of security.
Re:Let me be the first to say...
on
SHA-1 Broken
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· Score: 2, Informative
We cannot reasonably move to H(x)=MD5(SHA-1(x)). If you have a pair x, y such that SHA-1(x)=SHA-1(y) (i.e. a collision of SHA-1), then MD5(SHA(x))=MD5(SHA(y)). So H(x)=H(y) (a collision of H).
But don't worry (yet). There's still no known practical way to produce SHA-1 collisions.
Not necessarily. The NSA had differential cryptanalysis years before it was public. GCHQ had public keys well before RSA. Why are you so sure they don't have a working 4096 bit quantum computer now?
It is plausible, but it's just not particularly likely. The SIGINT agencies once had a huge lead on the open community simply because before the 1970s there was no real research happening in cryptography outside of the government; the likes of NSA and GCHQ, of course, had been breaking ciphers for decades. However, it's quite clear that now, after 25-30 years of an academic discipline of cryptography, the gap has shrunk. Quite how much we don't know, but, for example, Bruce Schneier speculates that it might be only a couple of years.
Who says it has to be done by a computer? The one-time pad is the weakest link, so you just put all your resources into obtaining it.
You could, of course, use various methods to try and steal the key/pad, and this is certainly a very real risk, but this is bypassing the encryption, not breaking it. There's a distinction between compromising the security and breaking encryption.
Any encryption can be broken - given enough resources... The trick is to make it so difficult that nobody finds out unless they are prepared to invest more than what you did (time, computing power, money, technology).
I agree with your comments about it only being necessary to secure something with respect to how much resources your adversaries are willing to invest in attacking it. However, it's not really true that all encryption can be broken, although this idea dates back at least to Edgar Allen Poe: "we say again deliberately that human ingenuity cannot concoct a cipher which human ingenuity cannot resolve."
First, we have the one-time pad, which has provable secrecy; even an army of quantum computers couldn't help you find the correct plaintext.
Secondly, while the one-time pad is not particularly useful in modern cryptography, we have algorithms, such as Triple-DES or AES, which (as far as is known) the amount of resources needed to break far exceeds the resources available to the entire of humanity. In these cases, it is not reasonable to say that "any encryption can be broken".
This person posted pictures of Wales' wife and child, insinuating that they were, respectively, a Fetal Alcohol Syndrome baby, and a porn model.
Almost certainly you meant "...respectively, a porn model and a Fetal Alchohol Syndrome baby";-)
But yes, resorting to these kinds of tactics is about as low as you can get on the Internet. However, there is the consolation that 99.9% of people are sane, and will realise that anyone who engages in this sort of campaign has very little credibility.
Go read the entire thread again. The first post asked for an evaluation of Wiktionary ("what's wrong with them?"). The second post gave an answer ("it sure looks incomplete to me"). To evaluate a resource is a perfectly valid thing to do, and there is no obligation to fix problems if the evaluation is negative, even if you have the capability to fix them.
Remember the context of the thread; this isn't someone just randomly moaning about a free resource not being as good as they'd like; this is a response to a query as to whether this "Universal Free Dictionary" project is necessary given that we already have a Wiktionary.
I'm a Wikipedia contributor, but I find the automatic response of "You're criticising a Wiki? How DARE you...stop whining and fix it yourself!" to be very irritating. It's perfectly reasonable for someone to evaluate or criticise a wiki project even if they're not interested in fixing the problems themselves. Or look at it this way; the thread was roughly this:
Ownermachine) Why do we need this "All Free Dictionaries" project? Isn't Wiktionary good enough? Xlv) It's incomplete. Batkiwi) Stop whining and fix it yourself!
I believe there is a standard (and pretty much phonetic) spelling. As to your observations, though, I'd hazard a guess that in regions where Swahili is less predominant, people might write Swahili using the spelling styles of another language, like French or English. Maybe?
I disagree with your rule of thumb. Have a look at Wikipedia's Featured articles. These entries are all of a reasonable standard and cover a large range of topics. I don't dispute that Wikipedia has a long way to go, but I don't think it's accurate to characterise it as a niche/cult Internet encyclopedia.
(PS. you talk about the 'unpaid so-called "volunteer"'. Why the quotes and the 'so-called'? Wikipedia editors are unpaid volunteers.)
I'm a Wikipedia fanatic, and in answer to your serious question, my guess is that something on the order of "almost all" of Wikipedia articles are quite naff -- this is based on lots of "Random page" expeditions. My view is that this will always be the case; there's always going to be some new emerging topic (e.g. pop culture) that will spawn hundreds of crappy stubs.
However, asking about the "typical" Wikipedia article is (strictly interpreted) asking the wrong question; a better question is to ask about how good Wikipedia is on the most frequently visited topics -- the 10% of articles that get 90% of the hits. In answer to this, my verdict would be "mediocre", but I'm quite picky.
The biggest gap in Wikipedia's mechanisms is (currently) a decent way to identify the good and bad articles; when this happens, it'll be a lot easier to map out quality sections (which undeniably exist).
Just a nitpick: while I agree with you that Wikipedia is unique in its presentation of an array of controversial theories, and that that's a good thing, the pre-WWII history of the breaking of Enigma isn't particularly controversial or unorthodox. Britannica Online has: "The Enigma code was first broken by the Poles in the early 1930s".
I reckon reviews are useful to help guide prior expectations, rather than final opinions.
I glanced at quite a few reviews for Matrix Revolutions before I went and saw it; the first time that I've ever read a review beforehand. Since the reviews were mostly negative, I was a lot less disappointed than the other people I went to see it with, and could enjoy it as a merely mediocre movie.
Slashdot Mirror
RSA-200 is 663 bits long. It's interesting to contrast it with RSA-640 (640 bits long). RSA-640 is shorter, so should be easier to factor. And unlike RSA-200, RSA-640 carries a cash prize of US$20,000 for its factorisation. So, a puzzling question is why did the team take on RSA-200 rather than RSA-640?
A virtual Enigma machine with thousands of rotors (etc) might be secure enough in actual practice, but would be a lot slower than current algorithms (even slower than, say, Triple DES). The Enigma was quite weak, though, compared to later machines: check out systems like SIGABA (US), KL-7 (NATO) or HX-63 (commercial) for some very secure rotor devices.
Regarding Enigma and the Allies...you're close: at the end of 1932, a Polish mathematician named Marian Rejewski deduced the Enigma rotor wirings using a combination of operator error, procedural flaws (the double indicator thing you mentioned), a key settings list obtained from a German cipher-clerk-turned-traitor (the spying), inspiration -- and a large dose of mathematical genius. See: Marian Rejewski on Wikipedia
So you're the guy who commissioned this Enigma? Nice!
You can find collisions for SHA-0 faster than expected, and it's claimed that you can do the same for SHA-1 (the attack hasn't yet been published, but it's pretty certain to be genuine). The SHA-2 algorithms (that is, any of SHA-224, SHA-256, SHA-384, or SHA-512) remain uncompromised. See: SHA article on Wikipedia.
Elliptic curve cryptography is (if you squint your eyes) a translation of older crypto techniques onto slightly more exotic mathematical objects. Rather than (say) integers modulo a prime, ECC uses a group of an elliptic curve over some finite field. But the new techniques are analogous to the old: Diffie-Hellman, ElGamal, DSA. The advantage is meant to be that keys can be a lot smaller for an equivalent level of security.
We cannot reasonably move to H(x)=MD5(SHA-1(x)). If you have a pair x, y such that SHA-1(x)=SHA-1(y) (i.e. a collision of SHA-1), then MD5(SHA(x))=MD5(SHA(y)). So H(x)=H(y) (a collision of H).
But don't worry (yet). There's still no known practical way to produce SHA-1 collisions.
Excuse my nitpicking, but you probably mean Cryptography and Cryptanalysis, which together form the field of Cryptology.
It is plausible, but it's just not particularly likely. The SIGINT agencies once had a huge lead on the open community simply because before the 1970s there was no real research happening in cryptography outside of the government; the likes of NSA and GCHQ, of course, had been breaking ciphers for decades. However, it's quite clear that now, after 25-30 years of an academic discipline of cryptography, the gap has shrunk. Quite how much we don't know, but, for example, Bruce Schneier speculates that it might be only a couple of years.
You could, of course, use various methods to try and steal the key/pad, and this is certainly a very real risk, but this is bypassing the encryption, not breaking it. There's a distinction between compromising the security and breaking encryption.
Any encryption can be broken - given enough resources ... The trick is to make it so difficult that nobody finds out unless they are prepared to invest more than what you did (time, computing power, money, technology).
I agree with your comments about it only being necessary to secure something with respect to how much resources your adversaries are willing to invest in attacking it. However, it's not really true that all encryption can be broken, although this idea dates back at least to Edgar Allen Poe: "we say again deliberately that human ingenuity cannot concoct a cipher which human ingenuity cannot resolve."
First, we have the one-time pad, which has provable secrecy; even an army of quantum computers couldn't help you find the correct plaintext.
Secondly, while the one-time pad is not particularly useful in modern cryptography, we have algorithms, such as Triple-DES or AES, which (as far as is known) the amount of resources needed to break far exceeds the resources available to the entire of humanity. In these cases, it is not reasonable to say that "any encryption can be broken".
Almost certainly you meant "...respectively, a porn model and a Fetal Alchohol Syndrome baby" ;-)
But yes, resorting to these kinds of tactics is about as low as you can get on the Internet. However, there is the consolation that 99.9% of people are sane, and will realise that anyone who engages in this sort of campaign has very little credibility.
Remember the context of the thread; this isn't someone just randomly moaning about a free resource not being as good as they'd like; this is a response to a query as to whether this "Universal Free Dictionary" project is necessary given that we already have a Wiktionary.
I'm a Wikipedia contributor, but I find the automatic response of "You're criticising a Wiki? How DARE you...stop whining and fix it yourself!" to be very irritating. It's perfectly reasonable for someone to evaluate or criticise a wiki project even if they're not interested in fixing the problems themselves. Or look at it this way; the thread was roughly this:
Ownermachine) Why do we need this "All Free Dictionaries" project? Isn't Wiktionary good enough?
Xlv) It's incomplete.
Batkiwi) Stop whining and fix it yourself!
I believe there is a standard (and pretty much phonetic) spelling. As to your observations, though, I'd hazard a guess that in regions where Swahili is less predominant, people might write Swahili using the spelling styles of another language, like French or English. Maybe?
Hmmm...No, I think it really is nimefurahi rather than nimefuraha; have a look at the Kamusi project. The noun is furaha; -furahi is the verb.
Well, I'm guessing the OP meant "Nimefurahi sana kukutana na wewe", which means, "pleased to meet you", iirc.
(PS. you talk about the 'unpaid so-called "volunteer"'. Why the quotes and the 'so-called'? Wikipedia editors are unpaid volunteers.)
I'm a Wikipedia fanatic, and in answer to your serious question, my guess is that something on the order of "almost all" of Wikipedia articles are quite naff -- this is based on lots of "Random page" expeditions. My view is that this will always be the case; there's always going to be some new emerging topic (e.g. pop culture) that will spawn hundreds of crappy stubs.
However, asking about the "typical" Wikipedia article is (strictly interpreted) asking the wrong question; a better question is to ask about how good Wikipedia is on the most frequently visited topics -- the 10% of articles that get 90% of the hits. In answer to this, my verdict would be "mediocre", but I'm quite picky.
The biggest gap in Wikipedia's mechanisms is (currently) a decent way to identify the good and bad articles; when this happens, it'll be a lot easier to map out quality sections (which undeniably exist).
There's something like an AES-style competition for stream ciphers? Sounds fun, who's organising it?
Just a nitpick: while I agree with you that Wikipedia is unique in its presentation of an array of controversial theories, and that that's a good thing, the pre-WWII history of the breaking of Enigma isn't particularly controversial or unorthodox. Britannica Online has: "The Enigma code was first broken by the Poles in the early 1930s".
I reckon reviews are useful to help guide prior expectations, rather than final opinions.
I glanced at quite a few reviews for Matrix Revolutions before I went and saw it; the first time that I've ever read a review beforehand. Since the reviews were mostly negative, I was a lot less disappointed than the other people I went to see it with, and could enjoy it as a merely mediocre movie.