APN (Access Point Name) is a term used in mobile network technology, specifically in the context of LTE networks. An APN is essentially a gateway between a mobile network and the internet or other IP-based networks, providing a way for mobile devices to connect to various services. (It is used to determine the PGW (Packet Data Network Gateway) that the mobile device should connect to, making the APN an essential parameter for configuring mobile devices to access the desired network services through the PGW.)
Different mobile network operators use different APNs for specific services. For instance, China Mobile uses the following APNs for their respective services:
"cmnet" for the Internet,
"IMS" for the IMS (IP Multimedia Subsystem) network,
and "cmiot" for IoT services.
A UE, such as a smartphone, can simultaneously connect to multiple APNs, establishing separate PDN Connections with corresponding PGWs. This enables users to access various services and networks simultaneously.
