[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]

Re: [tor-talk] Phones for Tor



> The issue with using the voice/SMS encryption on the cell network is
> that unless you can get an unregistered SIM card, then all of the
> traffic analysis "metadata" is easily tracked, stored and analyzed.

Anonymity and privacy are intertwined yet distinct. Some people
only have interest in privacy and do not care about the network
graph. Others need to go further and add anonymity.

> This is why I have been motivated to focus on IP-based voice and
> messaging solutions, particularly those that can work over TCP and Tor.

Those are needed too!

> and SMS solution

Sorry, I should not have put SMS in with the voice tech, it's clearly
different, what spec it is I do not know other than maybe a side
channel to GSM. Imagine some way to do key exchange for it... could
be a lot of texts, or a voice channel/pad.

> Specifically, you need the CDPD network service (aka
> the GSM "Fax" channel) to be available for use, and that just does not
> happen very much any more.

Presuming this is same as your 'CDPD', this is their take on it,
called CSD ...

http://www.cryptophone.de/en/background/cryptophone-technology/transport-technology/

If you don't want a data plan, this CSD tech is unavailable, and
you have software access to the mic i/o stream, it would seem
theoretically possible to compress, encrypt and send it over the
voice channel as you would with any landline modem. Or more crazy,
dongle with headset plug. As with you, I suspect it would be very
low quality, if you got it working over the rest of the phone/cell
path at all.

In the presence of cell provided IP transport (not coffeeshop
802.wifi), I admit such older tech is perhaps on its way out. For
now it may be a question of better price for your conversation,
minutes or megabytes. Free megabytes is less prevalent, and data
plans are not as often come with 'unregistered [prepaid] SIM'.


Some notes and links (unchecked)...

The history of cryptophone founding is interesting. It's probably
quite good, but the price and the model just isn't going to interest
many everyday people. Thus this thread to see what else.

The source code on cryptophone.de is also 10 years old.

http://www.hopenumbersix.net/mp3/16/cryptophone.mp3
https://en.wikipedia.org/wiki/Openmoko
https://www.schneier.com/blog/archives/2007/11/gsmk_cryptophon.html

http://www.caspertech.com/tech.php
http://www.cryptech.com/
http://www.gold-lock.net/
http://www.phonecrypt.com/
http://www.privategsm.com/
http://www.securegsm.com/
http://www.securstar.com/products_phonecrypt.php
http://www.tivi.com/en/tech/voipsoftcrypt.php
-- 
tor-talk mailing list - tor-talk@xxxxxxxxxxxxxxxxxxxx
To unsusbscribe or change other settings go to
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk