FreePBX v16, Asterisk v18. TCP transport is enabled in Asterisk SIP settings for PJSIP. The PJSIP extension transport setting is set to auto.
When I register the device on that extension with the transport setting on the sip device set to TCP, I can see that it is registering using TCP from the asterisk CLI.
Endpoint 999 is now Reachable
-- Contact 999/sip:[email protected]:54370;transport=TCP;ob is now Reachable. RTT: 188.571 msec
So far so good. However, when I look at it using PJSIP show endpoints, it looks like this.
Endpoint: 999/999 Not in use 0 of inf
OutAuth: 999-auth/999
InAuth: 999-auth/999
Aor: 999 1
Contact: 999/sip:[email protected]:54370;transport= 8c1c69524c Avail 188.571
It appears as though the transport= part is blank. UDP extensions don’t even have that transport= section, so presumably that’s how you know they are using UDP instead of TCP.
Looking at it using pjsip show endpoint 999 also does not show me what the transport is. The transport = line is also blank. Presumably that is just showing me what the extension is set to on FreePBX (auto), not how the device is registered.
The only command that shows me what the current transport is for an extension is pjsip show contacts, but I would think that pjsip show endpointsshould also show that.