112 - dentifying caller

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

John Henderson - 11 Oct 2003 21:24 GMT

I understand that the phone's IMEI is passed when making a GSM
emergency call to 112. But is any SIM information passed to
directly identify the caller (assuming a SIM's installed)? Any
network with a usable signal can handle any 112 call of course.

If not, it could mean delays before emergency services could ring
back (if they need to).

Can they ring back at all if no SIM's installed?

John

Reply to this Message

Jeremy Quirke - 12 Oct 2003 00:20 GMT

> I understand that the phone's IMEI is passed when making a GSM
> emergency call to 112. But is any SIM information passed to
[quoted text clipped - 7 lines]
>
> John

No identifying information is necessarily passed. If the the MS submits the
CC:EMERGENCY SETUP code in the RR:CHANNEL REQUEST access burst, the network
may not attempt the authentication sequence, and after a RR context is
established, the CC:EMERGENCY SETUP message shall be submitted by the MS,
which contains no identifying IMEI information.

Of course, the network could send MM:IDENTITY REQUEST with the request
Identity Type IE set to IMEI.

Reply to this Message

John Henderson - 12 Oct 2003 03:36 GMT

> No identifying information is necessarily passed. If the the MS
> submits the CC:EMERGENCY SETUP code in the RR:CHANNEL REQUEST
[quoted text clipped - 5 lines]
> Of course, the network could send MM:IDENTITY REQUEST with the
> request Identity Type IE set to IMEI.

Thanks for that info Jeremy. I was wondering why the ACA
recommends trying 000 before 112. So perhaps it's partly the
ability to quickly identify the caller (aside from the fact that
000 is less confusing for some people).

John

Reply to this Message