I am running Kamailio v. 5.1.2 with typical configuration for wss connections (default config + tls, websocket, nathelper modules), quite everything is running as should, but I am quite concerned about what I got on Homer server. My Kamailio is listening on port 4443 for TLS. Opening dialog runs as should, then UPDATE and BYE messages are received on 4443, but sent out on 5060. When I don't set up default port, 403 reply comes on a call. I'd like to know whether it is something defined by standard or it has a meaning and I should leave it as it is, or I should correct it somehow and then how. Also, if it has a meaning, then what it is.