>> "The advantage is that you would free up capacity on the
>> roads, you would reduce the congestion that we would otherwise
>> face and you would avoid the gridlock that you see in many
>> American cities today," he said.

You're not going to get the benefits of reducing congestion unless
drivers KNOW what price they are paying for driving.

>> "This is a prize well worth going for. We've got to ask
>> ourselves: would it work. Could it bring the benefits that
>> I believe it could bring, because it would make a real change
>> to the way we drive in this country."
>>
>> A satellite tracking system would be used to enforce the
>> toll, with prices varying from 2p per mile for driving on
>> a quiet road out of the rush hour to £1.34 for motorways
>> at peak times.

This thing needs to be able to display three things to the
driver at all times:

(1) The current rate per kilometer (or mile) being paid.
This allows people to complain that they are being taxed for driving
on their own lawn. It also lets them know about the expensive peak
times, so they can avoid them.

(2) The taxometer reading: the total accumulated taxes
for this unit. The value never goes down (like an odometer, and
except for the inevitable tampering), unless it rolls over, which
should not be possible (or at least not likely) within the period
between readings (how much would the taxes be on a car driven on
the most expensive freeways 24x7 at the speed limit between the
monthly readings? Make sure it won't overflow with several times
that amount.). You pay the difference between the current reading
and the last one when it gets read for tax purposes.

(3) The trip taxometer. Like a trip odometer, it increases
with the taxometer but it can be reset to zero at any time by the
driver, so the driver can reset it before a trip and read it at the
end, comparing the taxes on alternative routes. This reading is
not used in the tax calculation. It is only there for the convenience
of the driver.

You also need (4) the serial number of the taxometer, which never
changes. Guess what: this is the ONLY information you ever need
to take out of the taxometer. Route info never needs to be saved,
which will probably remove the REAL reason behind these schemes.

>> The Department of Transport says the scheme would be fairer
>> because those who travel greater distances would pay the most.

Explain why this is different from a gas tax or mileage tax,
which accomplish the same thing with a lot less equipment.

Gordon L. Burditt