Re: Really stupid question about offline address creation and the blockchain
Ok, thanks, that is helpful. However. To take your explanation one step further - Does that mean I could theoretically "see" a public address already existing on, say... blockchain.info, before it was technically ever generated offline?
That's the part I don't get. How is the address visible on these sites if the address was created offline? I can't see how they could already be there, that would a lot of data right? Thanks again and sorry for still trying to understand!
Yes, you can see every single possible address. These are visible because nothing an address does requires it to be "registered" onto the blockchain. An address is a special encoding of the RIPEMD160 hash of a SHA256 hash. To computers, these hashes are simply really big integers. Because we know the size of a RIPEMD160 hash (160 bits), we know what the biggest number that it can represent. This happens to be 2^160. Thus every address is already known because we know what all of the numbers between 0 and 2^160 are and can thus get the address without ever knowing the private key.That's the part I don't get. How is the address visible on these sites if the address was created offline? I can't see how they could already be there, that would a lot of data right? Thanks again and sorry for still trying to understand!