Foundation: the core is already software services
5G replaced the rigid, box-per-function core of earlier generations with a Service-Based Architecture (SBA): each network function (authentication, session management, mobility, policy) is a software service exposing an API over a shared bus, so functions can be deployed, scaled and updated independently in the cloud. This is the platform 6G builds on — and it means much of "6G core" is evolution, not revolution.
The cloud-native, API-driven core with independent network functions is established 5G technology. 6G inherits it wholesale — the question is what to add, not whether to keep it.
3gpp.org 2026-06-15A 6G system architecture study is underway in SA2, exploring a service-based, intent-driven core, an AI-native control plane, and terrestrial/NTN convergence ("system of systems"). The document identifier reported by secondary catalogs is TR 23.801; treat it as indicative until confirmed on the 3GPP portal.
wirelessbrew.com 2026-03 secondaryWhat "intent-driven" and "AI-native" actually mean
Intent-driven: instead of configuring thousands of parameters, an operator states an outcome ("guarantee 10 ms for this factory slice") and the network plans and enforces it. AI-native: machine learning is a first-class architectural element — for operations, optimisation, and the AI-as-a-service that the "AI & Communication" scenario implies — rather than bolted on afterwards. Both are genuine candidate directions with momentum, and neither is a finished 6G specification.
These concepts shape the architecture debate and appear across vendor and study material, but the normative design lands in Release 21. Present them as where 6G is heading, clearly distinct from what is decided.
qualcomm.com 2025-06 secondary| NF | Full name | Core role (5G) | 6G evolution direction | Status |
|---|---|---|---|---|
| AMF | Access & Mobility Management | Registration, mobility, reachability, NAS termination, paging | Extend for seamless terrestrial / NTN mobility | foundation |
| SMF | Session Management | PDU session setup/modification, IP allocation, QoS enforcement | Unified session model for communication + sensing data flows | foundation |
| UPF | User Plane Function | Packet routing, forwarding, QoS marking, traffic reporting | Intent-driven traffic steering; sensing data path | foundation |
| AUSF | Authentication Server | Primary authentication server, 5G-AKA / EAP-AKA′ functions | Post-quantum algorithm support (PQC key exchange) | foundation |
| UDM | Unified Data Management | Subscriber data, access authorisation, credential management | Federated identity across terrestrial and NTN domains | foundation |
| PCF | Policy Control | Policy rules, QoS framework, charging control | Intent translation — operator states outcome, PCF enforces | foundation |
| NEF | Network Exposure | North-bound API exposure to applications and third parties | AI/ML model exchange, sensing-as-a-service APIs | foundation |
| NRF | Network Repository | NF discovery and registration across the service bus | Dynamic service mesh for AI-native network functions | foundation |
| AI-NF ? | AI-native Network Function | — | New function class for ML model hosting, inference, lifecycle management — under study in TR 23.801 | candidate |
Where this connects
The core makes NTN convergence seamless, hosts the AI functions, and enforces the slices that meet the requirement targets. It is also where most security lives.