It seems like FS is unable to process a parallel forking originating in Kamailio (or others proxies of its type).

Kamailio does the routing logic, and creates various branches all with different request URIs but keeping the same CSeq and Call-ID and changing the branch parameters, but FS interprets these requests as the same and merges them running the forking impossible.

- I've seen replies that the CSeq should be increased, but this is not correct according to the RFC.

- Change Call-IDs, which should not be the case for parallel forking.

- And the only reported solution, change the T4 SIP timer to less than 4 seconds and put a sleep() on Kamailio for each branch. I personally don't consider this a solution as it plays with the timers.

Do you have any recommendations or ideas to solve this?
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