Примери коришћења One time pad на Енглеском и њихови преводи на Српски
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Now this game is truly a one time pad game.
Okay, so the one time pad is semantically secure.
This a semantic security game against the one time pad.
And, in fact, the one time pad is actually not such a secure cipher.
But in this segment we're going to talk about attacks on the one time pad.
It's called a one time pad It was designed by Vernam back at the beginning of the twentieth century.
So lets see what can we say about this quantity for the one time pad.
So, the stream cipher key or the one time pad key should never ever, ever, ever be used more than once. So.
Suppose you are givena message m and the encryption of that message using the one time pad.
But as we said the problem with the one time pad is that the secret key is really long. If you had a way of.
It's a very common mistake to use the stream cipher key, or a one time pad key more than once.
So recall that the one time pad encrypts messages by XORing the message and a secret key, where the secret key is as long as the message.
At the beginning of the 1940s, where the Russians actually used a one time pad to encrypt various mesages.
So a key in the one time pad is simply a random big string, it's a random sequence of bits. That's as long as the message to be encrypted.
And so, again, by what we said before,it just says that the one time pad has, perfect secrecy.
So what that says is that, for the one time pad, in fact, the number of keys, in K, shows the EKM, is equal to C. That simply is one, and this holds for all messages in cipher text.
As a challenge, he gets either the encryption of M0 orthe encryption of M1 under the one time pad.
The question to you is, if I have a message in a cipher-text, how many one time pad keys are there[inaudible] map, this message ends, so the[inaudible] C?
In fact, since the one time pad satisfies us with equality, the one time pad is an optimal, cipher that has perfect secrecy, okay? So basically, what this shows is that this is an interesting notion.
But the poor attacker can't do that because here maybe we've encrypted M1 using the One Time Pad so the attacker can't actually recover M1 because we know the One Time Pad is secure given just one cipher text.
We then talked about a way to make the one time pad practical by using a pseudo random generator that expands a short seed into a much larger message and the way a stream cypher worked, essentially using a pseudo random generator, was in the same way as the one time pad, basically, but rather than using a truly random pad, we used this pseudo random pad that 's expanded to be as long as the message from the short key that 's given as input to the generator.
In this segment, we're gonna look at attacks on the one time pad, and some things you need to be careful with when you use the stream cipher. But before we do that, let's do a quick review of where we were.
Because now the adversary is getting a one time pad encryption of M0 or M1 But in the one time pad we know that theadversaries advantage is zero, because you can't beat the one time pad.