Comment Re:Don't the laws of computing make it... (Score 1) 707
Actually, armed with contextual information, it might be possible to break a one time pad, not by exploiting the pad, but the humans.
First, the 'random' number source. If I know what the random number generator is, I can make guesses as to the probability distribution of letters in the pad.
Second, the language of transmission. If I know you're communicating in say English, I know the frequency that I can expect letters and even certain words to appear.
I now have at least two interesting probabilities to work with. So, in looking at the brute force generated messages, I can quickly eliminate ones that don't conform to the expected distributions.
OTP's are often susceptible to 'out of band' methods of cracking. The more I know about the context of the message, the manner it was generated, who what when and where it was sent to and from, the more accurate guesses I can make. It's almost impossible to get an exact crack, but the more messages sent using a certain one time pad, the more likely it is that a heuristic can be generated to analyze it.
First, the 'random' number source. If I know what the random number generator is, I can make guesses as to the probability distribution of letters in the pad.
Second, the language of transmission. If I know you're communicating in say English, I know the frequency that I can expect letters and even certain words to appear.
I now have at least two interesting probabilities to work with. So, in looking at the brute force generated messages, I can quickly eliminate ones that don't conform to the expected distributions.
OTP's are often susceptible to 'out of band' methods of cracking. The more I know about the context of the message, the manner it was generated, who what when and where it was sent to and from, the more accurate guesses I can make. It's almost impossible to get an exact crack, but the more messages sent using a certain one time pad, the more likely it is that a heuristic can be generated to analyze it.
