The partial article below is from:
It tells how to bring down bitcoin with a 51% attack
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So to bring down bitcoin you are going to have to beat them at their own game, fight fire with fire if you like, and use the mining and bitcoin protocol against them.
What you will need to do is build yourself your own mining operation just like the miners do but you are going to have to build one bigger and better than any of them, your mining operation is going to have to be able to equal everyone else’s hash rate plus a bit more (it is called the 51% attack by the way) and then you are going to start verifying blocks just like they do but you are not going to include any transactions in them! In effect, bitcoin will continue, but no one can transfer their bitcoins to other users.
Lets do some quick calculations so you can get a shopping list together, we have all the numbers because the blockchain and network hashrate are all public information. First we can see that the bitcoin network is capable of about 25 Thash/s (or 25,000,000,000,000 of those hash/guess’s per second) so we will have to do a bit better, lets say 26 Thash/s.
It would be good if we could use the new ASIC mining devices (Application Specific Integrated Circuit) were available, a single high-end ASIC device is said to be capable of up to 1,500 Ghash (or 1,500,000,000,000 hash per second) for $29,899 USD. 18 of those devices would net you a respectable 27 Thash/sec for just $538,182 USD but unfortunately they are not available yet.
Even when they are available, according to the unofficial wait list there are already at least 24 high-end devices on pre-order as well as a plethora (always wanted to use that word) of other lower-end devices totaling a staggering 53.9745 Thash/sec meaning that the total available hash rate will soon jump to somewhere in the region of 75 or more Thash/sec. This also has the effect of putting a time constraint on your 51% attack, it must be done soon, before the advent of the cheap ASIC devices in the next few months.
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