I'm quite happy about the volume and quality of responses I've received. So here is another question: What data generation rate should we aim for? I guess I should be more precise, given that costs are usually directly proportional to data rates, what are the minimum, hoped for, and high end data rates needed? For example, Tony Patti's RANGER has a very high data rate, but is big and costs more than two cases of beer. Is a good bit a second sufficient? 100 b/s? ??? Right now, I've only generated a few of Pr0duct Cypher's magic money tokens. So if I had a daemon process collecting bits for me in the background, then 3600 per hour is plenty. I am sure that when Perry uses digicash for online trading of eurodollars, he (and his user community) will need orders of magnitude more. But I'd expect them to be willing to pay at least an order of magnitude more for the gear too. I'd like to hear grounded justification for rates, and/or a rate/dollar tradeoff. Don't worry about the exact monetary exchange rates. Estimates in bits per second per case of beer are accurate enuff for this level of design. Thanks Pat p.s. I just got up to the chapter of Bruce's _Applied Crypto_ that addresses some of the approaches to this. It really is a FAQ for serious cypherpunks. Pat Farrell Grad Student pfarrell@cs.gmu.edu Department of Computer Science George Mason University, Fairfax, VA Public key availble via finger #include <standard.disclaimer>