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<DIV><FONT face="Times New Roman">Hi,</FONT></DIV>
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<DIV><FONT face="Times New Roman">I have tested ser with a T1 trunk GW not
behind NAT, but using fixed IP. I then disable the use of rtpproxy and
nathelper. However, when I use PSTN call to a SIP UA, only ringtones could be
heard but no voice passing through it.</FONT></DIV>
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<DIV><FONT face="Times New Roman">Does it mean that rtpproxy + nathelper must be
used even in the case when UA and PSTN GW are not behind
NAT/Firewall?</FONT></DIV>
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<DIV><FONT face="Times New Roman">Thomas</FONT></DIV></BODY></HTML>