[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@01D85B0C.FCF06DE0] My current behavior:

* Kamailio TM module is involved for parallel forking (https://www.kamailio.org/docs/modules/stable/modules/tm.html#:~:text=1.-,Ove...) * all branches are CANCEL-ed, it is not possible send CANCEL just to one specific branch [cid:image002.png@01D85B0C.FCF06DE0]

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.