APN is the Access Point Name , which is kind of like your phone’s password to the internet. You need the APN settings for you to be able to access AT&T’s LTE network.
Read moreWhat is APN type default Dun supl?
SUPL Apn Type: The SUPL means for secure user plane location . SUPL location type APN set up a secure connection with the location server in the operator’s network. Most of the time the default APN also serves the server for location.
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