Firstly, sorry if i say anything here that is too noob-ish, i'm a noob myself compared to most here, and you may already know some of what i say. These are just very basics to test if SME is connected to the net.
So, ok, to use putty, open it up, and leave everything as is, just put into the hostname field, the hostname of your server, then click "Open".
It should come up with a security alert, this is fine, just click "Yes".
Now, once you're in, put in "root" as the user, and your server password as password.
Once you are at the command line, try typing the following commands.
ifconfig
with the above, look at the last thing that comes up, if SME is connected to the net, it should have something called ppp0.
OR
ping -c 1 google.com
If you get a rply to the ping, then the server is connected.
Let me know how these go.
Cheers.