- sip can be used tcp or udp
- proxy should match with sip settings because if proxy is set it will be used for sip registrations and signals.
- rtp always UDP for now no options
- stun - always udp
- ice - udp no options
-firewall policy. UDP rules and depends on sip if uses tcp then need to look at tcp rules as well.
For good reliable network sip should use UDP for shorter response.
For not so reliable or 3G network or save battery in mobile phone, use tcp.
For new version of linphone I can not use UDP for sip not sure if any one has same problem? Also the remote provisioning stop working so I already back to older version. The proxy setting for tcp and udp in the new version does appear in the GUI but seems it has a bug.