ecash thoughts

[Simon Spero <ses@tipper.oit.unc.edu>]

1) Current ecash systems require live verification of coins, which 
will require banks to perform public key operations at around the 100K 
PKOP/s level, as well as all the headaches caused by the serial number 
lookup. 

Would anybody care to price up a system to handle this kind of traffic, 
assuming that coins can be given relatively short maximum lifetimes to 
keep the number of serial numbers in use within semi-reasonable limits. 
I'm wondering what the breakeven point is for only doing statistical 
sampling when verifying low value coins.

2) If ecash is used to create a new currency- i.e. the value of a unit of 
the ecash is not tied to any single existing currency, what should the 
value of one currency unit  be set at? (let's call it a Turing)

If the currency is run to be as anti inflationary as possible (e.g. 
backed by index-linked government securities), one Turing should buy the 
same amount of goods for a long long time, though relative prices may 
change. What value is likely to give the most convienient prices to the 
most goods? (e.g. +/- powers of two).

3) Not ecash, but still banking [noise]

I'm currently visiting at my parents house in England, which for the past 
18 years has had a really nice phone number. Unfortunately, BT split 
london into two area codes, and have reallocated the exchange number in 
the other one to citibank. Unfortunately, not many of their customers can 
quite cope with the concept of area-codes. Even more unfortunately, 
neither can BT or citibanks telcom group- we've had calls transferred 
from their switchboard straight through to us. 

Now, here comes the test for cp ingenuity - can you think of the best way 
to answer the phone to someone who things they've called a bank?

Ones I've used so far, when I've been really pissed off are:

Oh, I'm sorry - haven't you heard? They've filed for chapter 11. I'm from 
the Federal Reserve- I'm working with the recievers - can I possibly help 
you? [response was a disappointing "Good Heavens! Really?" ]

and the simple, yet subtle Lovecraftian terror of:

CitiBank, Nick Leeson speaking. [pause, giggle, must have a wrong number, 
click]

Any more suggestions? 

Simon