emergency call - fallback to call without SIM Re: capacitor to call the police without battery and SIM card *g* Re: Fun with Stolen/Lost Phones..

Robert Michel openmoko at robertmichel.de
Mon Dec 18 14:03:28 CET 2006

Salve Ben!

Ben schrieb am Montag, den 18. Dezember 2006 um 11:47h:

> On 12/16/06, Robert Michel <openmoko at robertmichel.de> wrote:
> >Without SIM card is the keyword. There are people got into trouble,
> >especialy in the mountains and they didn't made an emergency call
> >because their GSM network was not strong enough.
> >Only a few GSM user does know that then it help to remove the SIM
> >card to do a emergency call with any GSM network.
> In Australia they're considering banning 000 (emergency number in AU)
> calls from mobile phones without SIM cards. Apparently they've had
> tens of thousands of calls from such phones, but not a single one is
> genuine and most calls come just after school ends - so probably kids
> playing pranks. I don't think they've blocked this yet, but I'm not
> sure.

Arrrghhhh stupid politicans on the road? They should thought to 
map out IMEI (internationaly) after done a fake emergency call,
and to find out the owner of it...
but not to stop calls without sim card (IMSI).

In the book
J.Eberspächer/H.-J.Vögle (1999)
GSM Global System for Mobile Communication
on page 115 of the German edition stands
"Eine Mobilstation darf sich daher im "limited service mode" auch
auf eine solche Zelle festlegen (campen), wobei dann allerdings 
ausschließlich Notrufe erlaubt sind. Im "limited service mode" befindet
sich eine Mobilstation, wenn kein SIM vorhanden ist, die IMSI im Netz
unbekannt oder die IMEI gestperrt ist, oder auch, wenn die Zelle, die
das beste C1 besitzt, nicht zu einem erlaubten PLMN gehört.

IMEI International Mobile Equipment Identity
IMSI International Mobile Subscriber Identity
PLMN Public Land Mobile Network

Without SIM, a valid IMSI, even with a blocked IMEI and a forbidden
PLMN could the mobile terminal reach a "limied service mode" to 
do emergency calls.

The book is from 1999, I hope this detail hasn't changed.

So my idea to switch off the SIM is not neccessary to make
emergency calls without own network roaming.
A point that the OpenMoko/Neo1973 manunal (handbook) should
explain to the users (IMHO).


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