I want to be able to connect from my laptop to my desktop via SSH so I can work from the couch when I'm feeling lazy.
Currently, when I try, I get a message saying "connection refused"
There are really two parts to this question:
1) How do I turn on this feature?
2) How do I make sure that it can only be used by my laptop and not anyone out in the internet?
Here's a quick way to install the SSH server in Ubuntu:
sudo apt-get install openssh-server
But if I were you, I'd look at some documentation before (it's very complete and very straightforward).
I think you'll be particularly interested in Specify Which Accounts Can Use SSH, among other things.
1) How do I turn on this feature?
As @m.capobianco mentioned, you do the following to get openssh-server installed:
apt-get install openssh-server
Make sure that your desktop has a static IP (assigned by your home router), otherwise you will have to get up and check the ip (if it changed since last use).
2) How do I make sure that it can only be used by my laptop and not anyone out in the internet?
Easy, make sure no port forward is enabled from your router (external side) to your desktop. You are pretty safe behind your router, also SSH carries with it encryption and user based access.
Hope that clears that up.
