I have seen networks (e.g. in airports and hotels) that do not require a password to allow your mobile device to actually connect to the wireless network, however when you try to navigate to any website, it directs your browser to a specific page where you are required to enter a username and password or some sort key to go to any website.
I would like to set something like this up on our business network so that we could allow every person who wants to connect to have a different password and determine when and if that password expires. As it is now, we have a network-wide connection key, but if anyone were to guess/steal it, they would be able to connect indefinitely.
So my questions are:
Q1. What is this particular technology called?
Q2. What hardware/software is required to set this up?
Q3. Since a password is not required to actually connect, is the connection unencrypted?