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<DIV><FONT face="Courier New" color=#000000 size=2>Hi, regarding handling of CANCEL request,</FONT></DIV>
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<DIV><FONT face="Courier New" size=2>Please correct me if I am wrong,</FONT></DIV>
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<DIV><FONT face="Courier New" color=#000000 size=2>I have glare condition on how Opensips handled Cancel requests.</FONT></DIV>
<DIV><FONT face="Courier New" size=2>The problem is taht Opensips respond "487 Request terminated" strait after forwarding the CANCEL but it does not know if the targe UA will accept it.</FONT></DIV>
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<DIV><FONT face="Courier New" color=#000000 size=2>I think it should wait after the target UA to reply before, as this can create out of sync situation if there is a problem with the target.</FONT></DIV>
<DIV><FONT face="Courier New" size=2>in this senario the "200 OK" is received at the same time as the CANCEL is sent, in this case the target UA as the right to ignore the CANCEL because it as generated a final response.</FONT></DIV>
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<DIV><FONT face="Courier New" size=2>UA -----> CANCEL ------------------------> osips</FONT></DIV>
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<DIV><FONT face="Courier New" size=2>UA <------ SIP/2.0 200 canceling --------> osips</FONT></DIV>
<DIV><FONT face="Courier New" size=2> osips <--- 200 OK <-- UA</FONT></DIV>
<DIV><FONT face="Courier New" size=2> osips ---> CANCEL --> UA</FONT></DIV></DIV>
<DIV><FONT face="Courier New" size=2>UA <---- SIP/2.0 487 Request Terminated -> osips</FONT></DIV>
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