GTP-U and Charging Management Messages

Chapter 5 FortiOS Carrier : GTP message type filtering : Common message types on carrier networks : GTP-U messages : GTP-U and Charging Management Messages

SGSNs and GGSNs listen for GTP-U messages on UDP port 2152.

GTP‘ (GTP prime) is used for billing messages. It uses the common GTP messages (GTP Version Not Supported, Echo Request and Echo Response) and adds additional messages related to billing procedures.