

Bitcoin and the double-spending problem (2013) - bootload
http://blogs.cornell.edu/info4220/2013/03/29/bitcoin-and-the-double-spending-problem/

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modeless
> With a powerful botnet engaged in bitcoin mining, this attack becomes more
> likely

Botnets are irrelevant to Bitcoin mining these days. The datacenters full of
ASICs that miners are using now can easily outmine any botnet made of ordinary
PCs or servers no matter how large.

I see this article is close to 2 years old. A lot has changed since then.

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jpdus
I agree. Mods/Op should add "(2013)" to the title to avoid confusion (but as
others have pointed out, the article is not only old but wrong in important
points).

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martinko
>cracking a SHA256 hash function given to them dependent on the rate at which
mining is currently being done. The only known method to accomplish this is to
randomly test different prime number pairs in brute force fashion.

Bruteforcing a sha prefix has nothing to do with prime numbers. In the case of
bitcoin mining, an arbitrary nonce is included in a block. Different values of
this nonce are tested in order to get a resulting hash with the required
number of leading zeros.

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resonant
The author here demonstrates not only lack of knowledge but lack of
imagination, since with the ability to crack SHA (at mining speeds no less)
would open up a world of craziness, like being able to mine yourself a
Google.com certificate in under ten minutes.

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bachback
The paper this refers to [1]. Not waiting for confirmation has nothing to do
with double spend. Its a probabilistic measure - the original paper show the
poisson distribution, based on number of confirms. Beware of noobs with
algebra. "As we show in this work, the propagation of double-spending alerts
in the network would constitute a first important step towards efficiently
detecting doublespending." The bitcoin project is waiting for their pull-
request.

[1] [http://eprint.iacr.org/2012/248.pdf](http://eprint.iacr.org/2012/248.pdf)

