I've setup an SSH server on my Ubuntu desktop at home using a dynamic DNS service (NOIP). I have a wi-fi-only Android tablet running Android version 4.4.2.
Port 22 is forwarded, ufw is disabled currently.
On my tablet I can connect to other SSH servers, such as my college's server. However, I cannot directly connect from my tablet to my desktop; every attempt times out. But I am able to connect to my college's server and then SSH into my desktop from there. I'm also able to SSH into my desktop when I'm at home and I use the desktop's network IP address. I'm able to ping the public IP and receive responses.
But I'm at a loss to explain this behavior. It seems odd that I have to connect through another SSH server. Has anyone experienced a similar issue? Thanks in advance!
edit: adding error
failed to connect to name/ip-address (port 22):
connect failed:ETIMEDOUT(Connection timed out)