Apple is going to beat all competitors

Mikko Rauhala mjrauhal at
Fri Sep 7 23:03:03 CEST 2007

pe, 2007-09-07 kello 13:35 -0700, Shawn Rutledge kirjoitti:
> It's easy to think first of doing it over a data connection.  But I
> can imagine more of a signal-processing approach.

This has been hashed to death. Short of it: the GSM codec actively tries
to throw away anything that doesn't sound like speech. This is not very
analog encryption friendly, and we can't bypass the codec for voice
calls since that's in the closed TI firmware.

This is also a repeat, but for new people, I'll mention that does a proprietary encryption-capable GSM phone (through
GSM data); though the protocol is their own, they apparently have it
documented, and welcome others to do compatible implementations. (Their
source is also available, but for purely review and verification
purposes; it's not free and anyone doing a reimplementation would be
wise to avoid looking at it.) Thus for anyone interested in doing
encrypted calls with the Neo, it would perhaps be worth considering
using their ready-made protocol to leverage their installed base.

I haven't reviewed their protocol though, nor am I highly qualified to
do that. Also, there's the usual potential future issues with the
protocol being controlled by a single firm; basically that's just
something to consider for those who eventually get hacking on this.
Sadly, it's too big a project for me.

Mikko Rauhala   - mjr at     - <URL:>
Transhumanist   - WTA member     - <URL:>
Singularitarian - SIAI supporter - <URL:>

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