Robuta

https://www.kamailio.org/w/

The Kamailio SIP Server Project – The Open Source SIP Server

sip server open source kamailio project

https://mail-archive.com/koha-bugs@lists.koha-community.org/msg639201.html

[Koha-bugs] [Bug 39911] Fatal errors from SIP server are not logged

fatal errors sip server koha bugs