UBNT has an excellent product called the unifi captive portal that allows your guests to connect to your WiFi network without having to know your regular password. This solution works by creating an extra wireless network that is isolated from the rest of your private network. The captive portal then allows you to collect email and other information from your guest users and redirect them to a promotion URL such as your business website with the latest deal on it for example.
What is the UniFi portal?
How to set up the unifi captive portal
Setting up the unifi captive portal on your ubnt access point is a simple process. To get started, log in to your ubnt controller and select the “WiFi” tab from the main screen.
From here you will see a list of all your wireless networks and an option to add a guest captive portal for your WPA-Enterprise protected network.
When adding the captive portal, you will be prompted to enter a host name, choose the default language and if you wish to enable terms of service then click the “Enable Captive Portal” option. Finally you will need to choose whether to require a username and password or not, and to set a trial lockout period. Once configured you will be ready to give your guests free wifi in your Coffee shop, Hotel and other public places.