Hello, maybe I am missing something, but what about just using one of the standard reply codes for re-direction – 3xx? Cheers, Henning -- Henning Westerholt – https://skalatan.de/blog/ Kamailio services – https://gilawa.com<https://gilawa.com/> From: sr-users &lt;sr-users-bounces(a)lists.kamailio.org&gt; On Behalf Of Duarte Rocha Sent: Tuesday, February 9, 2021 12:39 PM To: Kamailio (SER) - Users Mailing List &lt;sr-users(a)lists.kamailio.org&gt; Subject: [SR-Users] Best SIP reply for service activation Hello, I'm currently developing a service on Kamailio where it's possible to configure redirections for a subscriber using a code. In order to implement that client should send an INVITE with a specific code on the Request URI and the redirection is configured. What should be the best way to answer this INVITE? A 200 OK will make the call answered and doesn't seem the best way. A negative reply (4/5/6xx) would work, but it seems strange to have the operation concluded with success and answering with a negative reply. I found "199 - Early Dialog Terminated" to be suitable, but the documentation suggests it should be used upstream. Thanks in advance for any suggestion. Cheers