Use telnet to check that VNC port is open

I am supposed to connect to a Mac VNC/ARD server. Let's say that the Mac VNC server has the hypothetical IP address 8.8.8.8.

I want to check if the Mac VNC server even listens to the default VNC port 5900.

So I ran:

telnet 8.8.8.8 5900

This times out. I arrive at the conclusion that the Mac VNC server doesn't use the default port (or some other substantial connection problem is the case). It is not a wrong password or wrong color setting, etc.

Is the above conclusion correct?

Yes it is correct...

If it were open you would get a blank screen, and if it were closed, it would say connection refused. Timing out is the same as closed in most cases.