SSH

i think that you just need to install the ssh server:
package: openssh-server

And yes you'll be able to connect from anywhere as long as your IP is reachable.

As the previous poster says, you need to install the "openssh-server" package. Here's the command you need to type (in a terminal window) in order to do so (it may ask you for your password):

  sudo apt-get install openssh-server

Now you should be able to connect from anywhere UNLESS your computer is protected by a firewall or behing a NATting device (most home routers, like Linksys).

If your computer is behind a firewall (or have one installed into it) you need to permit incomming connections on port 22/tcp. See your firewall documentation for details.

If it is behind a NATting device, you also have to setup the "port forwarding" fonction on the device to redirect incomming connections for port 22/tcp. See your router documentation for details.

For better security, I suggest you take a look at the openssh server configuration file (/etc/ssh/sshd_config) and make sure their is the following line in it:

Protocol 2

Make sure it is not commented out (no "#" in front of it) and that it is not "Protocol 2,1". The ssh protocol 1 is vulnerable to a particular type of attack.

Finally, for even more security, I recommend using cryptographic keys for authentication instead of passwords. And if you do so, you can turn off password authentication with "PasswordAuthentication no" in the configuration file.