Thanks for the great and insight-full responses Mike, Sean, and Chad.

PPP is not an option at this point due to equipment limitations. However, I
think T.38 header might be a good. I have to explore that and if it's not
then Radio Packets should teach me a lot.

Thanks again guys,
Bruce

On Sun, Dec 11, 2011 at 2:07 PM, Chad Osmond <[email protected]> wrote:

> Packet radio applications will do this. You can modulate to a wav play
> that wav to the far side and on the far side save to a.wav and.demodulate.
>
> My guess is 2400 would be the expected speed.
>
> Chad
> On Dec 10, 2011 5:13 PM, "Bruce N" <[email protected]> wrote:
>
>> Hi everyone,
>>
>> I have a situation where there is a PSTN line but there is no 56k Modem;
>> However there is a Linksys ATA with an FXO port attached to PSTN line and
>> registered to Asterisk. I want to stream "data" back and forth. No audio.
>>
>> I understand that is what a 56k modem best does in case of a PSTN analogue
>> line. I want to know if there is any method, algorithm (like using various
>> pitch sounds to send data) that I can take advantage of with or WITHOUT
>> using Asterisk? Currently, I am looking to send alpha-numeric in
>> 30-50 characters but later on, it can get larger so error correction,
>> error
>> detection (maybe using a hash digest), and as fast data-transfer as
>> possible (close to 56k) is ideal. I am assuming that 56k modems are the
>> fastest possible over analogue lines (since they have patented algorithms
>> and chips specifically built for this purpose)?!
>>
>> Currently in Asterisk 1.8x there is a morsecode() application which is
>> really cool but of course it's very slow. Also, there is no Morse code
>> reader for Asterisk (I could be wrong; please correct me if so). Or a very
>> basic thing I can do is to use DTMF and assign each letter a number and
>> transmit/decode on the Asterisk side but it will be really slow for my
>> purpose. So, something like that should do the job but since this is to be
>> machine automated I am sure it can be much faster using various pitch
>> sounds in much smaller intervals per code. Another example of this is some
>> programs that exist for amateur radio operators where a radio along with
>> GPS can be used to track location of a car.
>>
>> Any input, however technically in-depth, is much appreciated.
>>
>

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