NSSAI (Network Slice Selection Assistance Information)
Also known as: Network Slice Selection Assistance Information
NSSAI is the collection of S-NSSAI values a 5G UE requests, is allowed to use, or is configured with. Configured, Requested, Allowed, Pending and Rejected NSSAI variants are all carried in NAS signalling during registration and PDU session establishment, and they drive AMF selection via the NSSF.
Categories: Core Network
NSSAI 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.
To place NSSAI in the wider telecom-security picture, review NSSF, DNN, NGAP, N1, N2 and N11.
Related terms
Equipment
5G SBA control (NRF, SCP, NSSF, BSF, NWDAF)
Related topic hubs
- 5G Security 5G SBA, SEPP, SUCI, 5G-AKA, N32 and service-based interface security.
- Diameter Security 4G/LTE Diameter threats across IPX/roaming and DEA defenses.
- 5G NEF Security Network Exposure Function security in the 5G core.
- 5G Penetration Testing Pentesting the 5G core, SBA, SEPP, and gNB interfaces.
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.