Thread: one time pad breakable debate

  1. #256
    C++ Witch laserlight's Avatar
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    Quote Originally Posted by kryptkat
    the computer or the program has no way to know if or when the correct data is exposed.
    When attempting cryptanalysis against a cipher not equivalent to a one time pad, there are ways to program a computer to detect a plausible ciphertext, e.g., if the cryptanalyst knows the language of the plaintext and its character encoding, then the computer can be programmed to analyse for such characteristics. With sufficient ciphertext, brute force will then obtain the one most likely plaintext.

    But with a one time pad, there is no one most likely plaintext, regardless of the amount of ciphertext available. With knowledge of the language of the plaintext and its character encoding, the cryptanalyst can only obtain all such possible plaintexts of the corresponding length that have those characteristics, and all are equally likely.

    Quote Originally Posted by kryptkat
    even with unicity distance considered only the person that encrypted the small data would be the only one to recognize the correct contents instantly. anyone else would have to go on more external knowledge in order to have an educated guess about the contents of the unencrypted file.
    Yes, you do need some external knowledge. But the amount of external knowledge required to work out the plaintext encrypted with a one time pad is the same amount of external knowledge required to work out the plaintext without the ciphertext. Since the attacker would know the plaintext even without cryptanalysis, one can then reason that the cipher must be unbreakable: to "break" it, one must know the plaintext, yet that is the very thing that cryptanalysis sets out to obtain from the ciphertext.

    Frankly, there is no point in continuing this. Accept that you are wrong. If you refuse, then do as I say: write a paper and publish it. Prove the experts wrong. Even if they do not accept you now, maybe a later generation of experts will, and you will leave your mark in history, just like Claude Shannon.
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  2. #257
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    Quote Originally Posted by kryptkat View Post
    the computer or the program has no way to know if or when the correct data is exposed. when the computer or program exposes the correct data no matter what it may be the computers or the programs job is done .... that data is exposed cracked broken unencrypted what ever you want to call it. with one chance or exposure of one key makes no difference to the computer or software. at the point of exposure of the correct contents no matter if the individual is the attacker or recipient or the one who encrypted the one time pad or doing data recovery it still goes to external knowledge based data analysis. which may or may not be considered cryptanalysis.
    brute force will expose the correct contents by generating the correct key sequence once. if the attacker recognized the correct key it is then broken or cracked with external knowledge. therefore the correct term is improbable. because there is one chance in 256EEfilelength.

    should you get a porn generator i say enjoy it.


    you would get the correct corresponding plaintext or other file or whatever was vernamed. even with unicity distance considered only the person that encrypted the small data would be the only one to recognize the correct contents instantly. anyone else would have to go on more external knowledge in order to have an educated guess about the contents of the unencrypted file.

    I really can't stand this debate. Not because you're being so stupid, but because you don't even continue with any points we gave you. Read my post again. Tell me what part you didn't understand or didn't agree with. If there is no flaw in my post, then I am right per definition and that means that you are wrong.
    So find a flaw in my post, please.

  3. #258
    (?<!re)tired Mario F.'s Avatar
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    Look, this person is an obvious troll and it has been consistently behaving like a troll for years. There is really nothing new here. There was an inkling of hope in the beginnings of this thread, but quickly it became obvious it's the same old trollish attitude.

    The initial question has already been answered, and correctly answered. Even if this person keeps insisting 2 + 2 = 5, their opinion doesn't matter in the presence of all the scientific evidence. The thread should be closed or this troll will keep abusing the goodwill and patience of anyone involved.

    Alternatively. We should stop posting.
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  4. #259
    Just a pushpin. bernt's Avatar
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    Even if this person keeps insisting 2 + 2 = 5, their opinion doesn't matter in the presence of all the scientific evidence.
    The ministry of love would like to have a word with you .
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  5. #260
    Guest Sebastiani's Avatar
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    Quote Originally Posted by Mario F. View Post
    Look, this person is an obvious troll and it has been consistently behaving like a troll for years. There is really nothing new here. There was an inkling of hope in the beginnings of this thread, but quickly it became obvious it's the same old trollish attitude.

    The initial question has already been answered, and correctly answered. Even if this person keeps insisting 2 + 2 = 5, their opinion doesn't matter in the presence of all the scientific evidence. The thread should be closed or this troll will keep abusing the goodwill and patience of anyone involved.

    Alternatively. We should stop posting.
    Yes, and a creepy one at that. The sap doesn't even deserve the attention, IMO. I say let him be with his delusions...

  6. #261
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    Quote Originally Posted by Mario F. View Post
    The thread should be closed...

    ...Alternatively. We should stop posting.
    I don't think the thread should be closed.

    So far, the OP's persistence has been matched by the persistence of the responders, which I find amusing.

    If people have had enough of the OP, they should stop responding to them, and the thread will drop of the radar.
    OS: Linux Mint 13(Maya) LTS 64 bit.

  7. #262
    S Sang-drax's Avatar
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    Wow, this was a long read.

    MK27, having the user input a text and taking each character mod 2 does NOT give you a perfectly random key suitable for a one-time pad. This has been stated by many people and I am stating it again. As has been pointed out, it is even biased in the simplest sense as it does not produce equally many 0's and 1's.

    A MUCH better solution would be to pass the input text through a hash function. That would be pretty secure, but not theoretically unbreakable.
    Last edited by Sang-drax : Tomorrow at 02:21 AM. Reason: Time travelling

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    Kryptkat hasn't replied for a while... I wonder if he gave up on the attempt to make us finally see the light.

  9. #264
    Registered User kryptkat's Avatar
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    on the news they had a story where the students offered a teacher some tickets if that teacher made a basketball net from the middle of the playing field blindfolded. cwish. the teacher made the basket blindfolded from the middle of the gymnasium. come to find out that the students never had the tickets that they promised. why ? because the students ignored and dismissed the highly unlikely possibility that the teacher could actually make the basket from the middle of the gymnasium blindfolded. because the students thought that it is "impossible" to make a basket from the middle of the gymnasium blindfolded. instead of being "improbable" accounting for the highly unlikely chance that it could be done. there is a video of it on youtube.

    if you never purchase a ticket for the lottery this week then it would be "impossible" to win the money prize because there would be "0" chance of winning the lottery prize money. if you purchase one or more tickets then you would have a chance to win the money prize. however if you purchase "all" possible combinations then you would have a 100% chance of winning the lottery money prize of the weekly game. it may cost $200,000,000.00 to do so. then it becomes a question of "is it worth it". you would have to have a jack pot of more than $400,000,000.00 before you break even because half of it would go in taxes.

    Quote Originally Posted by laserlight
    to "break" it, one must know the plaintext
    and when i provide you with this exact situation were the user looses the key and has to brute force it to recover the data you dismiss it as nothing more than a memory test.

    i have other programs to work on and other books to read sometimes i do get busy. i still believe what i believe.

    i would like to remind you that i am the one that is not dismissing the fact that there is one key with one chance in however many to open the file. does it really matter how that key was obtained or fabricated ? by saying that it is "impossible" you are saying that even the key will not open the file. you are also depending on the obfuscation factor and ignoring the possibility that when the data is exposed it can be narrowed down to fewer choices. which for some reason you do not consider that cryptanalysis. the possibility of a lucky guess or an educated guess <with or with out external knowledge> could get the correct contents of the exposed data is also ignored and dismissed by you. i point that out and you call it troll behavior. what about your behavior when you run out of facts and figures or some one does not agree with your indoctrinated disposition you go straight for the insults. i remind you i have not resorted to insults and have only stated what and why i believe what i do. the brute forcers job is to expose that contents of the file then it job is done. broken exposed and it does not really matter if it is in a language you understand or not because one key fabricated opened it. only if you have something serious to hide or stand to loose a substantial amount of money would you continue with the illusion of unbreakable.

    debate closed.

  10. #265
    and the hat of int overfl Salem's Avatar
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    Yes, closed.
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