Data over normal GSM call

[Fabian Olesen]

On Mon, Apr 14, 2008 at 2:57 AM, Hans L <thehans at gmail.com> wrote:

>
> The standard tones allow up to 16 values to be represented at a time,
> so it would be like transferring data in base16 (aka hex or 4 bits at
> a time).  According to wikipedia, the minimum length of a tone should
> be 70ms, which would limit data transfer to roughly 56 bits/second.
> Of course this is very slow and unusable if you are thinking in terms
> of web browsing, but could be useful for transmitting small amounts of
> data such as URIs or other connection information(an IP address is
> only 32bits).  The URIs could be accessed immediately if the receiving
> end has a simultaneous internet connection, or saved for later.


This could actually work

But it would require that both ends have a specialised phonestack (openmoko
fx)
where some kind of protocol was inplemented for listening for DTMF with a
start and stop signal,
where the phone would know not to send the tones into the ear piece,
so that it would not scream into the other user's ears.



-- 

Mvh
Fabian Olesen

----
If it moves, compile it.
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