Re: e$ as "travellers check?

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>From: Jonathan Cooper  <entropy@IntNet.net>
>Date: Monday, August 29, 1994 6:45PM

>> > 	traveller's checks are an extremely easy way to defraud
>> > 	any bank that issues them,  what will happen to this
>> >  	difficulty factor if they are anonymous ?
>>
>> Digitally signed notes are not forgeable.

>   Right.

>   I doubt very seriously that there is anything on the planet that is
>*ABSOLUTELY* unforgable.   It all comes down to how much energy and
>resources one is willing to sink into the project.

This comment, unless I misunderstand it, supports (rather than refutes)
Perry's rebuttal to the claim that forging digital traveller's checks
would be "extremely easy."

Sticking in my nose where it doesn't belong,

JD


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> >> Digitally signed notes are not forgeable.
> 
> >   I doubt very seriously that there is anything on the planet that is
> >*ABSOLUTELY* unforgable.   It all comes down to how much energy and
> >resources one is willing to sink into the project.
> 
> This comment, unless I misunderstand it, supports (rather than refutes)
> Perry's rebuttal to the claim that forging digital traveller's checks
> would be "extremely easy."

   No - it just makes the point that there is almost nothing which is 
"not forgeable" with a suitable expenditure of effort & resources.

-jon
( THEY CAN STOP THE PARTY, BUT THEY CAN'T STOP THE FUTURE )
( --------------------[ entropy@intnet.net ]------------- )

Jonathan Cooper says:
>    No - it just makes the point that there is almost nothing which is 
> "not forgeable" with a suitable expenditure of effort & resources.

That depends on definitions. For instance, if I say "without stealing
a copy of our one-time pad, or using coercion on one or the other of
us, it would be impossible to forge a message between myself and my
correspondant who shares a one-time pad with me, given that we
properly use the one-time pad only once", I'm being reasonably correct --
no amount of expenditure of resources will do better for you than a
random guess.

It isn't true that "anything can be done given enough effort". Some
things cannot be done period, and some things cannot be done given
that we live in a finite universe.

Myself, I worry about the physical security of my keys a lot more than
about someone factoring them in most instances.

Perry