Usually different systems can use any authorities, but the usually have to have the the complete chain to the root installed in their key stores. So system Y has to know it can trust certs from CA X. So question is do you know where the key stores are located for each system and how to add certs to them. -------- Original message -------- From: Maciej Bylica <mbgatherer@gmail.com> Date: 8/17/17 11:37 AM (GMT-05:00) To: FreeSWITCH Users Help <freeswitch-users@lists.freeswitch.org> Subject: [Freeswitch-users] Separate CA authorities for SIP TLS Hello, I am about to setup TLS SIP interconnect between Cisco servers (C3945) and Freeswitch.CA server for Cisco devices is already in place (located on different cisco server).I want to proceed with CA Root certificate generation on Freeswitch server as well.My question is if i could use different CA authorities (separate for Cisco devices and the one for FS) for SIP TLS calls coming back and forth between Cisco and FS? ThanksMaciej.