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. 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. Is there something I've not set up correctly in my sshd_config file possibly? I'm able to ping the public IP. But I'm at a loss to explain this behavior. I've used both JuiceSSH and ConnectBot to no avail. Thanks!