<pre></pre><blockquote style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;" class="gmail_quote"><pre>It entirely depends on the technology used to interface to the PSTN. <br>You have not specified what technology/hardware you are using to connect<br>
to the PSTN.<br><br>For instance if you are using POTS(plain old telephone service - analog<br>copper fed lines), you do not get answer supervision back from the telco.-- <br></pre>
</blockquote><br>I am using tdm400 card with one fxo port. I am using analog line so I guess it's POTS <br>"analog cooper fed" line. So it is impossible to distinguish ringing from talking and billsec <br>must start when ringing begin due missing answer supervision from telco ? <br>
<br>Thanks for reply <br><br>Use Free Software <a href="http://www.fsf.org/">http://www.fsf.org/</a><br>-----------------------------------------------<br>Four essential software freedoms:<br>1) To study source code<br>2) To copy program<br>
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