Below are some prerequisites before logging into ATT router IP:- 1. The first requirement for the ATT router login is the internet connection. You must ensure that the connection between your router and network service is established. 2. The other thing that is necessary for the ATT router login is that you have to ensure that the connection you have chosen for the router is stable and consistent. 3. The last thing that you need for the ATT router login is a device like a tablet, computer, or a mobile phone.