I'm very curious as of what restricts the supply of bitcoins? basically, what mechanism prevents some computer to create new bitcoins, and pass them as valid to other bitcoin clients?
Bitcoin contains this magical little piece of code:
Code:
int64 GetBlockValue(int nHeight, int64 nFees)
{
int64 nSubsidy = 50 * COIN;
// Subsidy is cut in half every 4 years
nSubsidy >>= (nHeight / 210000);
return nSubsidy + nFees;
}
{
int64 nSubsidy = 50 * COIN;
// Subsidy is cut in half every 4 years
nSubsidy >>= (nHeight / 210000);
return nSubsidy + nFees;
}
If you try to create more than GetBlockValue coins (50, right now) when you get lucky and generate a block, all the other clients will reject it.
There are a bunch of other checks to prevent cheating (make sure you actually did the work to find a valid hash for the block, make sure all the transactions in the block are valid, etc), but that simple little piece of code is what restricts the supply.