14 Jan
2011
14 Jan
'11
9:29 p.m.
Aaron,
the usual problems with end-to-end encryption in GSM come into play: * as the voice path is not transparent but transcoded any number of times in the core network, you cannot simply encrypt the codec frames but gqwill have to initiate a CSD ('modem') connection. * not many networks support it anymore * calling rates are more expensive * you immediately leave a visible trail, since nobody else uses CSD
And no, neither is the ARM7 fast enough for any crypto, nor do we implement CSD at all.
--
- Harald Welte laforge@gnumonks.org http://laforge.gnumonks.org/
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