Data over normal GSM call
laforge at openmoko.org
Thu Apr 10 19:34:59 CEST 2008
On Tue, Apr 08, 2008 at 10:22:10AM -0400, Dan Staley wrote:
> Does anyone know if it is legal (in the standard TOS) with providers
> (such as ATnT) to send data over a normal phone call?
this is not possible, since regular voice calls for GSM are not
bit-transparent, i.e. the voice signal is coded and potentially re-coded
(transcoded) a number of time between the calling and receiving party.
Data calls over GSM are done using CSD. They also use quite a lot more
error correction than voice calls.
- Harald Welte <laforge at openmoko.org> http://openmoko.org/
Software for the world's first truly open Free Software mobile phone
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