To change the WiFi name/password on your Arris DG3450 modem, do the following:
-Connect a laptop or PC to the modem with an ethernet cable.
-Navigate to 192.168.0.1 and you will be directed to 1 of 2 screens.
1a) "First Time Setup" - create password for modem login. Note: this can be different than your WiFi password.
2a) Customize the WiFi Network name for the 2.4GHz and 5GHz network, as well as the password.
3a) Select your time zone and finish
Option 2: Modem has already been setup and you need to login to customize the WiFi info.
1b) Login with the following credentials: admin/<preshared key listed on modem>
2b) Navigate to Connection > WiFi > Networks and make sure Band Steering is DISABLED
3b) Edit the 2.4GHz network > customize the Network Name and Network Password > Save
4b) Edit the 5GHz network > customize the Network Name and Network Password > Save