Gx interface in a mobile network

Gx interface is a key reference point that enables communication between the mobile network gateway elements, (e.g. P-GW in 4G networks, or UPF in 5G networks), and the Policy and Charging Rules Function (PCRF).

Using Gx interface, the PCRF provide the mobile network gateway elements with the appropriate policy and charging rules to be applied to the subscriber's data sessions.