I can telnet from my desktop fine :
hostname:~$ telnet 139.x.x.x 25565
Connected to 139.x.x.x.
Escape character is '^]'.
When you say "a cloud server", is this on your own home network or somewhere on the internet?
If it's on the internet, then the F@ST modem isn't doing anything but connecting you to the internet and isn't "at fault", it's possible the server its hosted on is blocking the random port number you have chosen.
a cloud server - is a separate server outside (eg AWS)
As shown in the initial post it appears i can telnet to the port on the server in the cloud.
So wanted to know if anyone else on optus cable connects sucessfully to external minecraft servers ?
I've checked with Minecraft servers from my families Optus connection and have had no problem.
Telnet suggests there is no problem with the connection itself, because if Optus or the router was blocking the connection then you would see telnet also fail.
Are you sure AWS aren't blocking the non-standard port you have specified or in some way restricting connectivity to your AWS server?