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 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.

To place NSSAI in the wider telecom-security picture, review 5G, 5G SA, 5G NSA, 5G SBA, ACL and AES — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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