Why no remote unlock?

Matt W. Barrow wrote:

wrote in message
...
Matt W. Barrow wrote:


You have a million people within 500 feet (the range of a fob/garage
door
opened) of you at any one time?

Not relevant.

Completely relevant - it's the basis of how the devices are designed and
how
codes are arranged.

I highly doubt anyone ever seriously concidered the implications of being
within 500 feet of a million people -AT ANY ONE TIME- since it would
be physically impossible.

Downtown Manhattan.

Dividing a 500 foot circle into a million discrete areas gives each area
around a bit less than 11 inches on a side.

Not a chance.

Given trips to malls, the supermarket, etc. in metro areas, it wouldn't
take long to have been exposed to a million people within 500 feet.

The relevance is "at any one time".

Not hardly.

Only having that number of people AT ONE TIME is relevant in that ONLY then
can they set off your device.

With a probability of one if matching devices exist.

If you have a million devices and 1 match, hand those to a million
people, randomly select 500,000 people from the group to stand next to
and the probability is .5.

Select 10 out of the group and the probablility is .001.

Select 1 out of the group and the probablility is .000001.

(Not willing to play adolesant games any longer)

You consider probability to be adolescent?

--
Jim Pennino

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Military remote operations are common place. They use (a)symmetric
encryption systems xferred wifiand can be fortified with simple
biometric qualifiers (authentication). Cheap, doable, end of discussion.

WJRFlyBoy wrote:
Military remote operations are common place. They use (a)symmetric
encryption systems xferred wifiand can be fortified with simple
biometric qualifiers (authentication). Cheap, doable, end of discussion.

Guys with loaded guns at the entrance to military installations are
common place.

What's your point?


--
Jim Pennino

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Matt W. Barrow writes:

You have a million people within 500 feet (the range of a fob/garage door
opened) of you at any one time?

They're LONG odds, not impossibility.

If there are 200 cars within range in a parking lot, with a million codes, the
odds of two cars having the same code are about 1 in 5000. However, if you
commute twice a day in different parking lots with 200 cars in range for work,
there's about a 10% chance that you'll find another car with the same code at
least once a year.

This is still better than keys, which often have only a very small number of
"codes." In some cases there are only a dozen or so different keys for all
the cars of a specific model or even a specific group of models. On one
occasion, after locking myself out of a rental car, I was able to open the
door with a key for our own car, and the only thing the two cars had in common
was the manufacturer. On another occasion, I got into a car in the parking
lot that matched my key, paint job, etc., only to discover that it wasn't
mine.

Anyway, you need a lot more than one million different codes to be secure.

writes:

Given trips to malls, the supermarket, etc. in metro areas, it wouldn't
take long to have been exposed to a million people within 500 feet.

Roughly correct. More specifically, the odds diminish rapidly.

writes:

Dividing a 500 foot circle into a million discrete areas gives each area
around a bit less than 11 inches on a side.

Not a chance.

A million is a bit much for a 500-foot sphere (think in 3D, not 2D), but that
still yields only about 220,000 under the most extreme conditions.

Also, large crowds (as in demonstrations) can put very large numbers of people
within 500 feet, although not quite a million.

Mxsmanic wrote:
writes:

Dividing a 500 foot circle into a million discrete areas gives each area
around a bit less than 11 inches on a side.

Not a chance.

A million is a bit much for a 500-foot sphere (think in 3D, not 2D), but that
still yields only about 220,000 under the most extreme conditions.

And what magical power would suspend people in 3D?


--
Jim Pennino

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On Fri, 21 Mar 2008 02:55:04 GMT, wrote:

WJRFlyBoy wrote:
Military remote operations are common place. They use (a)symmetric
encryption systems xferred wifiand can be fortified with simple
biometric qualifiers (authentication). Cheap, doable, end of discussion.

Guys with loaded guns at the entrance to military installations are
common place.

What's your point?

I made my point.
--
Remove numbers for gmail and for God's sake it ain't "gee" either!
I hesitate to add to this discussion because I'm not an instructor,
just a rather slow student who's not qualified to give advice that
might kill someone.

Mxsmanic wrote in
news
Matt W. Barrow writes:

You have a million people within 500 feet (the range of a fob/garage
door opened) of you at any one time?

They're LONG odds, not impossibility.

If there are 200 cars within range in a parking lot, with a million
codes, the odds of two cars having the same code are about 1 in 5000.
However, if you commute twice a day in different parking lots with 200
cars in range for work, there's about a 10% chance that you'll find
another car with the same code at least once a year.

This is still better than keys, which often have only a very small
number of "codes." In some cases there are only a dozen or so
different keys for all the cars of a specific model or even a specific
group of models. On one occasion, after locking myself out of a
rental car, I was able to open the door with a key for our own car,
and the only thing the two cars had in common was the manufacturer.
On another occasion, I got into a car in the parking lot that matched
my key, paint job, etc., only to discover that it wasn't mine.

Anyway, you need a lot more than one million different codes to be
secure.


You don;t know how it works, fukkwit.


Bertie

Mxsmanic wrote in
:

writes:

Given trips to malls, the supermarket, etc. in metro areas, it wouldn't
take long to have been exposed to a million people within 500 feet.

Roughly correct. More specifically, the odds diminish rapidly.


Nope


Bertie