Hi. I have simple call flow: ``` UAS PROXY UAS 1 | INVITE | | |---------->| | 2 | 100 | | |<----------| | 3 | | INVITE | | |---------->| 4 | | 100 | | |<----------| 5 | | 180 | | |<----------| 6 | 180 | | |<----------| | 7 | | 183 | | |<----------| 8 | 183 | | |<----------| | 9 | CANCEL | | |---------->| | 10| | CANCEL | | |---------->| 11| 200 | | |<----------| | 12| | 200 | | |<----------| 13| | 487 | | |<----------| 14| | ACK | | |---------->| 15| 487 | | |<----------| | 16| ACK | | |---------->| | ``` One of our customers complains that TO-TAGs in 183 (packet 8) and 200(packet 11) are not equal(their devices see 3 to-tag during 1 dialog). I found in RFC 3261that it's ok(https://datatracker.ietf.org/doc/html/rfc3261#section-16.10). 183 is forwarded from UAS(UAS sets to-tag) and 200 is generated by Kamailio. This is why to-tags in 183 and 200 are not equal. Is it possible to use to-tag from master branch(ofc if we have received a reply from UAS and we have this tag)? -- Reply to this email directly or view it on GitHub: https://github.com/kamailio/kamailio/issues/3021 You are receiving this because you are subscribed to this thread. Message ID: &lt;kamailio/kamailio/issues/3021(a)github.com&gt;