phone fun, was GeoIP database issues and the real world consequences

Owen DeLong owen at
Thu Apr 14 21:46:48 UTC 2016

> On Apr 14, 2016, at 14:01 , John Levine <johnl at> wrote:
>> OK, let us suppose I want to be a law biding, up right American and use 
>> only a cellphone for the "right" area.
>> I drive a big truck OTR.  I usually know what part of which state I am 
>> in, but I frequently do not know which part of what state I will be in 
>> in 24 hours.
>> What should I do?
> As previous messages have explained, mobile 9-1-1 uses a variety of
> GPS and tower info to determine where you are.  Telcos, stupid though
> they may be, have figured out that people with mobile phones are
> likely to be, you know, mobile.

Now if they could only figure this out for VOIP clients.

I realize that there are fixed-location VOIP phones and they may be the majority,
but I also know that there are quite a few of us with VOIP clients that are as
mobile as our mobile phones, sometimes more so since my VOIP client doesn’t turn
into $2/min. when I enter the wrong country. Amusingly, 128k free data from T-Mo
as a mobile hot spot in many countries is quite adequate for a VOIP client while
making a call on the phone would cost $$.

> If you drive a big truck, you're likely to spend a lot of time on
> major highways, and many of those highways have signs that tell you
> what to dial to contact the appropriate police for that road, e.g.
> *MSP on the Mass Pike.

Depends on where you are. I’ve never seen such a sign anywhere on any major highway
in California and mobile 911 calls in this state often get “interesting” routing.
Fortunately, I’ve never encountered a dispatcher that required answers to more than
one additional question in order to comply with my request that they route to the
correct agency (I usually start off with enough information to tell them I know why
I want to speak to the agency I am specifying, such as “I’m reporting an incident
on {US/Interstate/State Hwy specification, e.g. US 101}, please transfer me to CHP”
(CHP = California Highway Patrol, which has dispatch jurisdiction for all state and
federal highways within California).

OTOH, I’ve been in parts of Canada where the signs merely specify that there is no
911 service beyond that point without offering any alternative. Of course most of those
signs were encountered well after my mobile stopped having any service whatsoever,
so I always found them mildly amusing. Most of them are a giant picture of a motorola
Brick phone from the late ‘80s with the message “Leaving 911 service area”.

I can’t find an appropriate image to reference in a google search, but I assure you
that they were common place, at least last time I was in the Yukon.


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