Hello
I have a theoretical question regarding how sha1() works.
Is it theoretically possible for sha1() to return the same output for two different input strings?
thanks
usage of sha1() function
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davidklonski
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Re: usage of sha1() function
Theoretically, yes, it is possible for there to be a collision.davidklonski wrote:Hello
I have a theoretical question regarding how sha1() works.
Is it theoretically possible for sha1() to return the same output for two different input strings?
thanks
The odds are 2^(n/2), where n, in the case of SHA1, would be 160 (bits). (It would be 2^n, but there is an issue called the 'birthday paradox', which is important here, which lowers it to 2^(n/2))
Thats over one septillion possibilities. Since the peak of the distributed RSA challenge saw 7 billion keys per second, that means it would take distributed.net roughly 1.9 million days to find it.
I'd say thats pretty solid.
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