Gx interface is between GGSN and PCRF (Policy Charging Rules Function) ,and Gx interface base on the Diameter protocol, GGSN act as the PCEF (Policy and Charging Enforcement Function),through the Gx
interface and the PCRF realize the PCC(Policy and Charging Control) function

very good document. i would like to have it.

This document is very well done

very useful. i would like to have it.

useful document, thanks