Right now the bitcoin network is calculating at about 500 GHash/second. Only 1 hash is needed to process an entire batch of transactions (a block). Well, technically it is 2 SHA hashes that are needed per block. So 499,999,999,998 of the hashes calculated in the next second will be wasted.
It gets worse. That is 500 GHash per second. Over the approximately 10 minutes between blocks, only two of those 300,000,000,000,000 hashes that were calculated will actually be used even.
Of course, there is a reason for this. Hashing to obtain a relatively unique result is called a "proof of work" and is the method that Bitcoin uses to ensure that the amount of currency issued occurs only at the levels specified in the source code. http://en.bitcoin.it/wiki/Proof_of_work So far, that method has been the only one found so far that works as the transaction processing system for a decentralized payment network.
It gets worse. That is 500 GHash per second. Over the approximately 10 minutes between blocks, only two of those 300,000,000,000,000 hashes that were calculated will actually be used even.
Of course, there is a reason for this. Hashing to obtain a relatively unique result is called a "proof of work" and is the method that Bitcoin uses to ensure that the amount of currency issued occurs only at the levels specified in the source code. http://en.bitcoin.it/wiki/Proof_of_work So far, that method has been the only one found so far that works as the transaction processing system for a decentralized payment network.