On Wed, 10 Apr 2002, Tim May wrote:
>> How come? True, if a bill is idealized as being planar, you'll have
>> trouble on the plane. Spatial diversity will take care of that.
>> Otherwise, a common note has plenty of surface to do your thing on.
>> Especially at higher frequencies, like UHF and be
On Thu, 11 Apr 2002, Eugen Leitl wrote:
> I could imagine airlines screening for this, though, as a big RFID splash
> would invite you to become a target for "random" searches, and a
> prospective target for confiscation.
Better yet, rather than nuke your rfids, try to extract them out of the
cu
On Thursday, April 11, 2002, at 07:07 AM, Trei, Peter wrote:
> [1. Agreed, this thread has lost steam.
> 2. It always amazes me how often people on this list will handwave and
> speculate on subjects which a few minutes with Google will settle. Too
> often, we're like the medieval academics who
> --
> From: [EMAIL PROTECTED][SMTP:[EMAIL PROTECTED]]
> Sent: Thursday, April 11, 2002 11:24 AM
> To: [EMAIL PROTECTED]
> Subject: RE: Detectable cash notes a fantasy
>
> > Go and read 'Repent Harlequin! Cried the Tick-Tock Man'
On Wed, 10 Apr 2002, Tim May wrote:
> How come? Because I am assuming the transponders are in the same
> position on each bill. If you want to posit some "spatial diversity"
> model, that helps, but not but a huge amount. This sounds too science
> fictionish to actually deploy (transponders are
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Tim wrote:
Faustine wrote:
> If, when I came here, I had made the deliberate choice to make an
> effort at "getting along" by emphasizing our similarities instead of
> differences, I dare say the motivation to dissect-and-destroy every last
> comment
On Wednesday, April 10, 2002, at 11:58 AM, Faustine wrote:
> If, when I came here, I had made the deliberate choice to make an
> effort at
> "getting along" by emphasizing our similarities instead of differences,
> I dare
> say the motivation to dissect-and-destroy every last comment I ever
>
On Wednesday, April 10, 2002, at 12:25 PM, Sampo Syreeni wrote:
> On Wed, 10 Apr 2002, Tim May wrote:
>> (A stack of bills, or cards, will have extremely poor radiation
>> patterns
>> from any but the top or bottom bill, and probably their patterns won't
>> be good either.)
>
> How come? True,
30 seconds in a microwave on high, stir and rotate tray...
-Original Message-
From: Michael Motyka [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, April 10, 2002 8:24 AM
To: [EMAIL PROTECTED]
Subject: Re: Detectable cash notes a fantasy
Tim May <[EMAIL PROTECTED]>
>
>On Tues
On Wed, 10 Apr 2002, Tim May wrote:
>A meter-sized antenna is not going to efficiently radiate
>sub-millimeter-sized waves.
But it does give you brutal directivity. If you're truly working with
sub-millimeter waves, you might be able to discriminate between individual
bills with a phased array t
On Wed, 10 Apr 2002, Tim May wrote:
>So, if in fact we _are_ talking about each $20 bill having such a
>transponder, then why are our arguments about how easy it will be to
>shield against remote probing not valid?
Because the economics do not work. People simply aren't
knowledgeable/interested
On Wednesday, April 10, 2002, at 11:22 AM, Trei, Peter wrote:
> The argument against shielding is that it is obnoxious that I
> (or anyone) should have to go even further than I already do to
> maintain even a fraction of the privacy which was naturally available to
> every person 150 years ago.
On Wednesday, April 10, 2002, at 11:22 AM, Trei, Peter wrote:
> Detection range turns out to be function of antenna size - the reader's
> antenna, not the one on the transponder. So if you have a big (eg,
> doorframe size) antenna, you can do a lot better than the 'valid bill
> detector' on the c
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Tim wrote:
>Everytime I comment on your citations, you go into a snit about how
>"Gramps" is insulting the "whippersnappers."
No, it's all about the condescending tone you take when you use "your many
years of experience" as leverage against anyone
On Wed, Apr 10, 2002 at 02:22:04PM -0400, Trei, Peter wrote:
| > If a stack of bills containing these transponders are supposed to be
| > read from afar, way beyond what a "valid bill detector" is likely to be
| > engineered to do, I'd like to see the physics worked out.
| >
| Detection range
> --
> From: Tim May[SMTP:[EMAIL PROTECTED]]
> Sent: Wednesday, April 10, 2002 1:59 PM
> To: [EMAIL PROTECTED]
> Subject: Re: Detectable cash notes a fantasy
>
> On Wednesday, April 10, 2002, at 09:27 AM, Trei, Peter wrote:
> >> For
On Wed, Apr 10, 2002 at 10:59:32AM -0700, Tim May wrote:
| On Wednesday, April 10, 2002, at 09:27 AM, Trei, Peter wrote:
| >> For paper money failure rates will probably be high anyway.
| So, if in fact we _are_ talking about each $20 bill having such a
| transponder, then why are our arguments
On Wed, 10 Apr 2002, Tim May wrote:
>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 me
On Wednesday, April 10, 2002, at 09:27 AM, Trei, Peter wrote:
>> For paper money failure rates will probably be high anyway.
>>
>>
> Perhaps, perhaps not. Remember, the primary app for this is
> anti-counterfeiting.
>
> "Sir: ALL your $20 bills are failing authentication. Please wait
> while I ca
On Wednesday, April 10, 2002, at 08:23 AM, Michael Motyka wrote:
> Or more.
>
> Not to mention that if you didn't want your money chirping its presence
> every time a bad actor pinged it you could just disable the transponder
> in the money :
>
> mechanical pressure or repeated bending
> high vo
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
Tim May writes:
> I'll go back to lurking, as this "thread," so to speak, is not
> interesting to me.
>
> (More interesting is reading Chris Hillman's page with his Categorical
> Primer on it, http://www.math.washington.edu/~hillman/papers.html. And
> to BL and JA, I downloaded O'CAML and picke
"Trei, Peter" wrote:
>
> > Michael Motyka[SMTP:[EMAIL PROTECTED]]
> >
> >
> > Tim May <[EMAIL PROTECTED]>
> > >
> > >On Tuesday, April 9, 2002, at 10:54 AM, Trei, Peter wrote:
> > >> Putting RF Tags in cash is one of those ideas with Unintended
> > >> Consequences.
> > >> Muggers would love havi
> Michael Motyka[SMTP:[EMAIL PROTECTED]]
>
>
> Tim May <[EMAIL PROTECTED]>
> >
> >On Tuesday, April 9, 2002, at 10:54 AM, Trei, Peter wrote:
> >> Putting RF Tags in cash is one of those ideas with Unintended
> >> Consequences.
> >> Muggers would love having a way of determining which victims
Tim May <[EMAIL PROTECTED]>
>
>On Tuesday, April 9, 2002, at 10:54 AM, Trei, Peter wrote:
>> Putting RF Tags in cash is one of those ideas with Unintended
>> Consequences.
>> Muggers would love having a way of determining which victims are
>> carrying a
>> wad, as would many salesmen (and JBTs
On Wed, 10 Apr 2002, Eugen Leitl wrote:
> The tags are passive. All tags (whether inductive or electrostatic) must
> be energized from the outside. The pumping energy can be shielded, as can
> the RF emission of the tags itself. The environment is noisy. The tags
> send simultaneously from the
On Wed, 10 Apr 2002, Trei, Peter wrote:
> So, yes, at the moment they can't scan your wallet very easily. But
> this technology is developing as all others are. I don't know about
> dealing with many similar tags more or less simultaneously, but some
> of the discussed apps for stock tracking req
> Tim May[SMTP:[EMAIL PROTECTED]]
>
> On Tuesday, April 9, 2002, at 10:54 AM, Trei, Peter wrote:
> > Putting RF Tags in cash is one of those ideas with Unintended
> > Consequences.
> > Muggers would love having a way of determining which victims are
> > carrying a
> > wad, as would many salesm
On Tuesday, April 9, 2002, at 07:43 PM, Faustine wrote:
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> Tim wrote:
>
>> Physics-wise, it's a jiveass fantasy. No way are there "micro-strips"
>> readable from a distance in today's currency, and very likely not in
>> the
>> next 20 years.
>
On Tuesday, April 9, 2002, at 07:06 PM, Mike Rosing wrote:
> On Tue, 9 Apr 2002, Tim May wrote:
>
>> Physics-wise, it's a jiveass fantasy. No way are there "micro-strips"
>> readable from a distance in today's currency, and very likely not in
>> the
>> next 20 years. (I don't dispute that a car
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