Weird Tech question.....

[dogmush]

......or How Efficiently the NSA is tracking you.

The wife and I are vacationing in Cambodia right now.  I checked with Verizon, and while my phone would work here, it's more money then I care to spend.  So when I got here I bought a Cambodian SIM (they sell them at the airport and all over for tourists). $10 got me some minutes, some texts and 3.5 Gb of data for a month.  I shut my phone down, slammed the Asian SIM in, booted up, signed in and bada boom.  I can make phone calls (to Cambodian phones) they can call me (on my new Cambodian 10 digit number), texts, data everything is great.

Here's where it gets weird.  I'm getting SMS messages from the states.  From my friends.  If they text my Stateside Verizon number, in about 30 secs (I timed it) the message will get to my phone, with my Cambodian SIM in.  The message will come from an Asian number, but my phone will know (somehow) who it's from, pull the right name from my contacts, and assign them to the Asian number.  My Verizon SIM is in my camera case for all of this and wifi is turned off.  It's coming over the Cambodian Cell network.

How the heck?

[Hawkmoon]

I thought Verizon didn't use SIMs?

[dogmush]

They have since the 4G LTE infrastructure came out. Something about different radios.

[dogmush]

No one?

I don't want to ask Verizon because I'd have to admit I switched SIMs. Pretty sure that's against TOS.

[TechMan]

I am taking a wild guess.  There is another number that is associated with your phone besides the SIM number.  That number is connected to your SIM card and your real phone number.  You phone was powered up with your actual SIM so the network captured that info and then registered the change with the new SIM.  Again a SWAG.

[TechMan]

Oh BTW I have enjoyed your trip pics on the book of face.

[RoadKingLarry]

Oh BTW I have enjoyed your trip pics on the book of face.

Why the hell didn't we get to see any of them here?

[dogmush]

Why the hell didn't we get to see any of them here?

Because I'm posting from a cambodian SIM card on my phone,  and usage the photobucket app.

I have a half formed pensive post I'll put up when I get to a real computer.

As for the text thing. That's not a bad SWAG, but I didn't hot swap the SIMs. Phone was turned off. The only thing I can think is that the phone hardware itself has some kind of hard coded ID like a MAC address that links it in Verizon'so computers even without the SIM. It's weird,  and a little creepy that they can find my handset that well.

[AJ Dual]

Yes. Your phone has a MAC address for it's WiFi adapter. There's also a hard coded IMEI number in the phone, regardless of what SIM card it has. And it's not very tin-foily because any modern digitial cell service has to be able to know which phone it's talking to anywhere in the world. Since people could catch a boat or a plane to some other part of the world, and be sitting in the same cell or a nearby cell of the same city or region, and placing a call, it wouldn't do any good if these numbers weren't unique, and a value that goes well into the hundreds of billions before there's any chance of a repeat.

https://en.wikipedia.org/wiki/International_Mobile_Station_Equipment_Identity  Usually it's under the battery if your phone has one that comes out. Otherwise it can be found somewhere in the settings menu or "phone information" or "about this phone" etc.

Plus any of your apps or services running on the phone could have a "call home" function in them to reach out over the net and contact the carrier, or Google, the servers of a game you play that has any kind of network connectivity, like friend sharing, or in-app purchases... whatever.

[TechMan]

Yes. Your phone has a MAC address for it's WiFi adapter. There's also a hard coded IMEI number in the phone, regardless of what SIM card it has. And it's not very tin-foily because any modern digitial cell service has to be able to know which phone it's talking to anywhere in the world. Since people could catch a boat or a plane to some other part of the world, and be sitting in the same cell or a nearby cell of the same city or region, and placing a call, it wouldn't do any good if these numbers weren't unique, and a value that goes well into the hundreds of billions before there's any chance of a repeat.

https://en.wikipedia.org/wiki/International_Mobile_Station_Equipment_Identity  Usually it's under the battery if your phone has one that comes out. Otherwise it can be found somewhere in the settings menu or "phone information" or "about this phone" etc.

Plus any of your apps or services running on the phone could have a "call home" function in them to reach out over the net and contact the carrier, or Google, the servers of a game you play that has any kind of network connectivity, like friend sharing, or in-app purchases... whatever.

Thanks, that was what I was looking for.  IMIE was not on the top of the brain this morning.

[Fitz]

iPhone?

[dogmush]

iPhone?

GS6