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<TITLE>Declined INVITE invokes multiple Decline's at Proxy</TITLE>
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<P><FONT FACE="Times New Roman">Hello,<BR>
<BR>
I am using openser v1.0.<BR>
<BR>
I have a problem with the following SIP scenario with openser:<BR>
<BR>
- A invites B to a call session, B declines the invitation<BR>
</FONT>
<BR><FONT FACE="Times New Roman">The message trace shown below is just part of the message trace produced for the above scenario displaying message frames in sequence F43, F44 ... through F64</FONT></P>
<P><FONT FACE="Times New Roman">Initially everything works as expected: INVITEs, Trying (100) and Ringing 180 messages are routed correctly from A to B and from B to A via the intermediate proxies (this is not shown below). While still 'Ringing', B decline's the call (sends a Decline message) message: F44 in trace below. This also initally routes OK. </FONT></P>
<BR>
<P><FONT FACE="Times New Roman">But the call flow for this scenario is expected to terminate at message: F55 once the 'Decline' has routed its way back from the B-Party to the A-Party and a final 'ACK' is sent by the A-Party to the previous proxy: Proxy-1.<BR>
<BR>
But what actually occurs is that openser running on Proxy-1 automatically resends a 'Decline' at message F56 identical to the 'Decline' it first sent at message F46. This in turn prompts further ACKs and 'Decline's until it finally times out at message F107 (not shown below).<BR>
<BR>
It appears that openser saves the original message and attempts to retry/resend the 'Decline' message when prompted by an ACK. This continues for several cycles with ACKs and Decline's being sent and received around the system until a timeout occurs. </FONT></P>
<BR>
<P><FONT FACE="Times New Roman">The above behaviour also occurs for the following scenario:<BR>
<BR>
- A invites B to a call session, B responds with a Busy<BR>
<BR>
Can you help me to:<BR>
<BR>
- understand what is going on<BR>
- terminate what appears to be an open 'transaction' for the 'Decline' and prevent further 'Decline's and ACKs being sent around the system.<BR>
</FONT>
<BR><FONT FACE="Times New Roman">Best regards,<BR>
Andrew<BR>
</FONT>
<BR><FONT SIZE=2 FACE="Courier New">--------------</FONT>
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<P><FONT SIZE=2 FACE="Courier New">A-Party Proxy-1 Proxy-2 Proxy-3 B-Party</FONT>
<BR><FONT SIZE=2 FACE="Courier New">10.1.195.134:50 10.1.195.134:50 127.0.0.1:5070 127.0.0.1:5080 10.1.195.208:50</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">|<nging 180 F43<| | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| |<----------------------------- Decline 603 F44<|</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| |>F45 ACK ------------------------------------->|</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| |>F46 603 Decline ------------->| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| |<--------------------- ACK F47<| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | |<cline 603 F48<| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | |>F49 ACK ----->| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | |>F50 603 Decli>| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | |<----- ACK F51<| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| |<------------- Decline 603 F52<| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| |>F53 ACK --------------------->| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">|<cline 603 F54<| | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">|>F55 ACK ----->| | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| |>F56 603 Decline ------------->| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| |<--------------------- ACK F57<| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">|<cline 603 F58<| | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">|>F59 ACK ----->| | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| |>F60 603 Decline ------------->| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| |<--------------------- ACK F61<| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">|<cline 603 F62<| | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">|>F63 ACK ----->| | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| |>F64 603 Decline ------------->| |</FONT>
<BR><FONT SIZE=2 FACE="Courier New">| | | | |</FONT>
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