EZ Pass followup.
Trei, Peter
ptrei at rsasecurity.com
Tue Jul 20 11:07:39 EDT 2004
This may be of interest to the folks discussing EZ pass.
On ne.transportation, there is a thread regarding
the subject, titled:
Surveillance Equipment on I-95?
The most interesting post follows.
Peter Trei
--------------------
From: john_s at no.spam
"John F. Carr" wrote:
> In article <cdhb6c$l7r$3 at pcls4.std.com> <mailto:cdhb6c$l7r$3 at pcls4.std.com>,
> Michael Moroney <moroney at world.std.spaamtrap.com> <mailto:moroney at world.std.spaamtrap.com> wrote:
> >I noticed several unusual sensors on I-84 SB in Connecticut, just before
> >and at a weigh station that's just north (IIRC) of Exit 71 These are
> >overhead on a gantry, and some look like the old-style (large) security
> >camera without a lens. I figure they are somehow related to catching
> >trucks bypassing the weigh station but how exactly do they work?
>
> I assumed they were part of the weigh-once scheme that is spreading
> around the country. A truck having been confirmed to be legal in one
> state may bypass other weigh stations in that state or a cooperating
> state. Before the weigh station a transponder is interrogated and the
> truck is not required to stop if the computers like it.
>
> Sometimes there are signs saying "follow signal in cab" or something
> like that.
It is part of the weigh station bypass system. <http://tinyurl.com/4hqc5> If
the truck has a participating transponder, it can usually skip the weigh
station if everything is in order. The transponder will display a green
light to bypass, a red means a trip to the weigh station. The light stays on
for a few minutes so that compliance can be checked, if needed. Some
stations have weigh-in-motion equipment to verify that the weight
There are two major weigh station bypass programs in North America: PrePass
and NorPass. You can see what states they are used here:
<http://tinyurl.com/48twn> Connecticut's weigh station(s) have been
compatible with NorPass for several years and they just joined NorPass as a
full member a few weeks ago. <http://tinyurl.com/3oj99>
NorPass doesn't have any fees once you buy your transponder. (PrePass
charges for each bypass with a daily maximum). All systems use a compatible
transponder, and it is possible to buy a transponder that also speaks the IAG
protocol so it can be used at E-ZPass locations for tolls (after the
transponder is registered with E-ZPass).
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