When you work under very secured network, You always needs to open firewall requests by one way or the other. And sometime this task is taken care by your Infrastructure services team.
You probably know about the Curl command which is inbuilt utility provided by Unix servers.
We can test the firewall opening with Curl command as below:
curl -v telnet://127.0.0.1:8080
When you run above command, You will receive below message which says port is open.
If by chance, Port is not open then you will receive below error message.
You can run and practice curl command using Cygwin into your Window system.