>Hmmm.....
>
>I don't think they have static IP addresses.

They do if they have DSL.

> I'm thinking that on installation, an encrypted internal password is assigned and that used.

Of course that will work too.

> The license server I'm using is practically bulletproof; I'm not concerned about that.

Yeah, but what about their connection? And your ISP? And the DNS authority for your domain? There are lots of places a connection can go bad...

>I don't intend to maintain a constant server connection, just check it periodically. That being said, is this a reasonable model?

Yup.