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--></style></head><body lang=FR link="#467886" vlink="#96607D" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;mso-ligatures:none;mso-fareast-language:FR'>Hi all,<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;mso-ligatures:none;mso-fareast-language:FR'>I’m working on a call flow using OpenSIPS with the B2B modules, aiming to <b>analyze call progression on Leg B</b> before allowing it to complete on Leg A.<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;mso-ligatures:none;mso-fareast-language:FR'>Here’s the scenario:<o:p></o:p></span></p><ul type=disc><li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo2'><span style='font-size:12.0pt;mso-ligatures:none;mso-fareast-language:FR'>OpenSIPS receives a call (Leg A)<o:p></o:p></span></li><li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo2'><span style='font-size:12.0pt;mso-ligatures:none;mso-fareast-language:FR'>OpenSIPS initiates a new call to the destination (Leg B)<o:p></o:p></span></li><li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo2'><span style='font-size:12.0pt;mso-ligatures:none;mso-fareast-language:FR'>While monitoring SIP replies from Leg B (e.g., 183, 180, 200), OpenSIPS may decide to <b>terminate the call at any point</b> and return a custom SIP response (e.g., 987 Voicemail Detected) to Leg A instead of forwarding the final reply.<o:p></o:p></span></li></ul><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;mso-ligatures:none;mso-fareast-language:FR'>The problem is:<o:p></o:p></span></p><p class=MsoNormal><b><span style='font-size:10.5pt;font-family:"Helvetica Neue";color:#0E0E0E;mso-ligatures:none;mso-fareast-language:FR'>I can’t prevent the 200 OK from Leg B from being relayed to Leg A.</span></b><span style='font-size:10.5pt;font-family:"Helvetica Neue";color:#0E0E0E;mso-ligatures:none;mso-fareast-language:FR'><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;mso-ligatures:none;mso-fareast-language:FR'>I’ve tried using b2b_logic, but I can’t seem to intercept and block the final reply in time.<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;mso-ligatures:none;mso-fareast-language:FR'>Has anyone successfully implemented a similar flow or knows how to stop the forwarding of 200 OK to Leg A within the B2BUA context?<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;mso-ligatures:none;mso-fareast-language:FR'>Thanks in advance for any guidance.<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;mso-ligatures:none;mso-fareast-language:FR'><o:p> </o:p></span></p><p class=MsoNormal>OtterTek<o:p></o:p></p></div></body></html>