On Wednesday, April 10, 2002, at 07:44 AM, Trei, Peter wrote: > Tim: I advise you to get up to speed on this stuff.
I think I'm more up to speed on small detectors than I want to be (through my involvement with an ultrawideband company). But I misunderstood the discussions about currency being tagged vs. wallets with transponders. (Which I don't see Joe Sixpack ever adopting in our lifetimes, for multiple of the usual reasons.) > >> Further, placing the notes in a simple aluminum foil pouch, or a wallet >> with equivalent lining, would cut any detectable signals by maybe 30-50 >> dB. >> > Most people don't, and won't do this. You may not worry about the > sheeple, > but I do. > I figure the sheeple will mostly take of themselves. And, in fact, they do, through a kind of collective recoiling from certain things, coupled with monkeywrenching, deliberate misuse, etc. The "interesting" part of the space of uses of digital money is certainly, for me at least, not in the "wallets with transponders so that Big Brother can track your cash." Selective disclosure of information (SDI) and all that stuff. If wallets carry RF ZKIPS communication capabilities, as they probably will, the designed range will be small. And the wallet will probably have to be "enabled." What I would picture is something like this: Alice approaches a kiosk or transfer point of some sort. She pulls out her SmartWallet (TM), enters a PIN or fingerprint, which turns on the device for some number of seconds, aims it at (or actually inserts it into) a receiver, and a ZKIPS protocol begins firing back and forth. (Some here have said the Hitachi tags are passive. Fine. Useful for things like tracking railroad boxcars or shipping containers, where attaching a battery would be more expensive, less reliable, and too much work. But for a smart card or Smart Wallet, there will be active processing _anyway_ (as the account balance changes, as PINs are entered, etc.), so having a small battery, perhaps light-rechargeable (*), is OK. (* Smart cards already have this. I have a thin credit card calculator from the early 80s that works this way.) And as in that standard example of "capabilities," she doesn't say "please look inside my wallet and take what you need." Rather, she authorizes a specific amount or limit (she extends a capability right, rather than an access right). The engineers of such SmartWallets will not give them more range than the protocol needs. Extra range costs money. If Alice is expected to insert her Smart Wallet into a receptacle (for security, if for nothing else), initiating the protocol from several meters away is not in the cards, so to speak. If someone is arguing that such Smart Wallets will merely be passive "announcers" of bank balances, this is just too naive to waste discussion time on. Good luck selling such a system. --Tim May "That the said Constitution shall never be construed to authorize Congress to infringe the just liberty of the press or the rights of conscience; or to prevent the people of the United States who are peaceable citizens from keeping their own arms." --Samuel Adams
