Hello, yesterday it was already answered from Alex that this is possible with Kamailio on the sr-users list. Please follow up there on this thread. The development list is about development topics, usage questions and discussion should be done on sr-users. Thanks and regards, Henning -- Henning Westerholt - https://skalatan.de/blog/ Kamailio services - https://gilawa.com<https://gilawa.com/> From: sr-dev &lt;sr-dev-bounces(a)lists.kamailio.org&gt; On Behalf Of VESELOVSKY Pavel Sent: Thursday, April 28, 2022 2:35 PM To: sr-dev(a)lists.kamailio.org Subject: [sr-dev] Kamailio functionality clarification - call forwarding no replay (call is ringing but not answered) Hallo all, I would need help with Kamailio. I hope, you can give me some hints. I would like use Kamailio for CFNRy feature call forward no replay, i.e. - call is forked to multiple destination - 180 is received, call is ringing, but not answered, no 200 OK is received from some destination - after predefined time (CFNRy timer), only this specific branch has to be rerouted to another destination Expected behaviour is described in this flow: [cid:image001.png@01D85BA1.68083420] My current behavior: - Kamailio TM module is involved for parallel forking (https://www.kamailio.org/docs/modules/stable/modules/tm.html#:~:text=1.-,Ov…) - all branches are CANCEL-ed, it is not possible send CANCEL just to one specific branch [cid:image002.png@01D85BA1.68083420] My questions: - is it possible to CANCEL just specific branch? - is it possible start timer just for specific branch? - do you think is it possible somehow implement this feature with Kamailio? Thanks a lot in advance for any comment. Pavel.