Hi all,

On Sat, May 04, 2013 at 12:56:58PM +0100, Amir Taaki wrote:
> This is really creepy. I discovered that every mobile phone has an IMEI
> number, and that it is illegal to change this number. There's a device

It depends on the country, in the UK it's an offence:
https://en.wikipedia.org/wiki/International_Mobile_Station_Equipment_Identity#IMEI_and_the_law

To change IMEI for current phones (iPhone/Android based) is really difficult,
but for the older ones, it's quite technically easy (but still illegal).

> on the antenna of mobile phones which is illegal to modify. This IMEI
> number is mandated by government rules.
>
> If everyone uses mobile phones in the future, this means general purpose
> computers which all have a unique assigned ID that cannot be changed.
> Every computer would be in people's pockets and tracked via this
> government issued ID.

BTW, I've just remembered to this Cory Doctorow presentation:
https://www.youtube.com/watch?v=HUEvRyemKSg

> I discovered this number because here in the UK, the ISPs offer 2
> services: a decent service for mobile phones and a terrible service for
> computer USB dongles. You can take the mobile phone SIM and use it in an
> unlocked (hacked) laptop dongle and use it for 1-2 weeks before they
> block it based on the manufacturer's IMEI number.

In Slovakia you can buy old phone (with the IMEI that it's possible to change)
from bazaar completely anonymously, then in Czech Republic you can buy
completely anonymous SIM card (including data roaming), so with this
combination you can achieve quite a good level of privacy. But of course
GSM localization is still possible and some deanonymization techniques can be
used, especially if you carry your phone every day from your home to your
office or have some other repetitive patterns that can be used for
deanonymization.

Czech anonymous SIM cards with data roaming (that works everywhere in Europe
and including the UK) costs about 800 Kc (31 €) monthly for 1.2 GB data.
I've already activated it for some of my friends who travelled around Europe
and wanted to access to the Internet anonymously.

Pavol
--
______________________________________________________________________________
[Pavol Luptak, Nethemba s.r.o.] [http://www.nethemba.com] [tel: +421905400542]