Ben Laurie <[EMAIL PROTECTED]> writes: >>>Not entirely clear what you mean by the "issuing bank" here, but I'm >>>hoping you don't mean that the bank issues the device - that would be >>>very tedious. >> >> Tedium is something that computers do very well. They don't care >> about how much work they have to do. The only issue is whether we >> induce too many serialized public key operations, and thus too much >> delay. > > Sure, but multiple physical devices aren't my computer's problem, > they're my problem.
Ah, I see what you mean. Sadly, I don't think there is much to be done about that, but I think that (personally) I'd only end up with two of the things. If they can be made credit card sized, I don't see this as worse than what I have to carry now. >>>This would preclude, for example, offline transactions. >> We used to live in an era where offline transactions were >> important. Now that you can get online literally anywhere, and now >> that merchants pretty much are required to check card validity and >> funds availability online anyway, that's no longer an interesting >> concern. I can't think of the last time I was involved in an offline >> transaction -- even folks at street fairs can now afford GPRS and >> similar communications for their veriphone (and similar) units. > > There are reasons to want to do offline transactions and to not have > intermediaries that go beyond mere connectivity. Anonymity being the > one of most concern to me, but I'll wager there are others. Anonymity is a concern to me, too, but I suspect that it is hard to get anonymity in a credit card transaction using current means, even if the merchant isn't online. Pseudonymity, perhaps. Perry --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]