The PDN Gateway (P-GW) hosts the following functions (see 3GPP TS 23.401 [17])
- Per-user based packet filtering (by e.g. deep packet inspection)
- Lawful Interception
- UE IP address allocation
- Transport level packet marking in the downlink
- UL and DL service level charging, gating and rate enforcement
- DL rate enforcement based on APN-AMBR
