BSF (Binding Support Function)

BSF in context

The mobile core carries subscriber sessions, mobility and policy. 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.

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

To place BSF in the wider telecom-security picture, review PDN, UPF, SBA Token Forgery, PGW, UDR and DRP: each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

• PDN
• UPF
• SBA Token Forgery
• PGW
• UDR
• DRP
• IAMF
• MSC

Related topic hubs

• 5G Security 5G SBA, SEPP, SUCI, 5G-AKA, N32 and service-based interface security.
• 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.
• 5G NEF Security Network Exposure Function security in the 5G core.

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.