PDN (Packet Data Network)

PDN in context

The mobile core is where subscriber sessions, mobility and policy live. In 4G it is the EPC (MME, HSS, S/PGW); in 5G it is the Service-Based Architecture with AMF, SMF, UPF, AUSF, UDM and the NRF. Core exposure is the difference between a single-subscriber leak and a fleet-wide breach.

Subscriber identifiers (IMSI, SUPI, MSISDN, IMEI) are the anchor for authentication, charging, lawful interception and fraud analytics. Any protocol or interface that leaks a permanent identifier is treated as a serious privacy defect, which is why 5G introduced SUCI concealment on the air interface.

To place PDN in the wider telecom-security picture, review PGW, BSF, Subscriber, UPF, SMSC and UDR.

Related terms

• PGW
• BSF
• Subscriber
• UPF
• SMSC
• UDR
• PCRF
• EIR

Related topic hubs

• 5G Security 5G SBA, SEPP, SUCI, 5G-AKA, N32 and service-based interface security.
• 5G NEF Security Network Exposure Function security in the 5G core.
• 5G Penetration Testing Pentesting the 5G core, SBA, SEPP, and gNB interfaces.
• 5G Security Training Training on 5G core, SBA, N32, SUCI and radio security.

More from the TelcoSec Glossary

Browse the full TelcoSec Glossary, the Ultimate Guide to Mobile Network Security, or the P1 Arsenal of telecom-security tools.