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<DIV><FONT face=Arial size=2><SPAN
class=712232010-25072005>Hi,</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=712232010-25072005></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=712232010-25072005>I've recently
encountered some problem with my SIP service whereby i call out to a specific
number and i encounter a one way voice. If i'm the initiator, i cannot hear the
other party but he can hear me. At first i thought it was a return route issue
(as i'm going thru NAT) , so i switch my SIP to a public IP but i still face the
same problem. Its really only that specific PSTN number that i have dialed
facing this problem. The only difference that i can think of is that PSTN
number is on a different route. I did a NGREP from my SIP server for the PSTN
number that works (2-way voice) and the Number that doesn't work (1-way voice) .
The only difference is there is an extra :</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=712232010-25072005></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=712232010-25072005>NGW -->
Proxy</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=712232010-25072005> SIP/2.0 183
Session Progress..Via: SIP/2.0/UDP </SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=712232010-25072005>Proxy --> SIP
Device</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=712232010-25072005> SIP/2.0 183
Session Progress..Via: SIP/2.0/UDP</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=712232010-25072005></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN
class=712232010-25072005></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=712232010-25072005>for the PSTN number
that works (the one with 2-way voice).</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=712232010-25072005></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=712232010-25072005>Anyone has idea what
does the Session Progress is for ? Or what problem am i facing
?</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=712232010-25072005></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=712232010-25072005>Thanks a mILLION
!</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=712232010-25072005></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN
class=712232010-25072005>Regards,<BR>Sam</SPAN></FONT></DIV></BODY></HTML>