Ah, I see, thanks for the corrections.
Some of the discussion and concern over performance may relate to the eventual size of the P2P node network. How large do you envision it becoming? Tens of nodes? Thousands? Millions?
And for clients, do you think this could scale to be usable for close to 100% of world financial transactions? Or would you see it as mostly being used for some “core” subset of transactions that have special requirements, with other transactions using a different payment system that perhaps is based on Bitcoin?
Hal
Re: Bitcoin source files attached
Private email with Hal Finney · 2 messages · from 19 November 2008 · with Hal Finney, Satoshi Nakamoto
Read in Satoshi Mail Archive source
100,000 block generating nodes is a good ballpark large-scale size to think about. Propagating a transaction across the whole network twice would consume a total of US$ 0.02 of bandwidth at today’s prices. In practice, many would be burning off excess allocated bandwidth or unlimited plans with one of the cheaper backbones. There could be millions of SPV clients. They only matter in how many transactions they generate. If they pay 1 or 2 cents transaction fees, they pay for themselves. I’ve coded it so you can pay any optional amount of transaction fees you want. When the incentive subsidy eventually tapers off, it may be necessary to put a market-determined transaction fee on your transactions to make sure nodes process them promptly.
To think about what a really huge transaction load would look like, I look at the existing credit card network. I found some more estimates about how many transactions are online purchases. It’s about 15 million tx per day for the entire e-commerce load of the Internet worldwide. At 1KB per transaction, that would be 15GB of bandwidth for each block generating node per day, or about two DVD movies worth. Seems do-able even with today’s technology.
Important to remember, even if Bitcoin caught on at dot-com rates of growth, it would still take years to become any substantial fraction of all transactions. I believe hardware has already recently become strong enough to handle large scale, but if there’s any doubt about that, bandwidth speeds, prices, disk space and computing power will be much greater by the time it’s needed.
Satoshi