Description
RSNPN, or Registered SNPN, is a critical identifier within the 5G system architecture for Standalone Non-Public Networks (SNPNs). An SNPN is a network deployed for private use, such as by an enterprise or factory, which operates independently of public network operator credentials (like PLMNs). The RSNPN specifically denotes the particular SNPN where a User Equipment (UE) has successfully completed registration and authentication procedures. This registration process is defined in 3GPP TS 24.501, which specifies the Non-Access Stratum (NAS) protocol for 5G systems. Upon successful registration, the UE and the network mutually acknowledge the RSNPN identity, establishing a secure context for subsequent communication.
The architecture supporting RSNPN involves core network functions like the Access and Mobility Management Function (AMF) and the Authentication Server Function (AUSF). When a UE attempts to access an SNPN, it provides a Network Identifier (NID) combined with a PLMN ID (which for an SNPN is a dedicated, standardized value). The AMF, in coordination with the AUSF, authenticates the UE based on credentials specific to that private network, such as credentials from the SNPN operator or a credential holder. Successful authentication and registration lead to the establishment of an RSNPN context. This context is used for session management, mobility management, and policy enforcement within the confines of that specific private network.
The role of RSNPN is fundamental for network selection, access control, and service continuity within private 5G deployments. It ensures that a UE only accesses services and resources authorized for that specific SNPN. The identifier is used in NAS signaling messages to maintain the registration state and is crucial during mobility events, such as handovers between cells belonging to the same SNPN. It enables the network to apply specific network slices, QoS policies, and security settings configured for that private network. For network operators and enterprises, RSNPN provides a clear demarcation, allowing multiple isolated private networks to coexist without interference, even if they share underlying physical infrastructure.
Purpose & Motivation
RSNPN was introduced in 3GPP Release 16 to address the growing demand for private, standalone 5G networks. Prior to SNPNs, private network deployments often relied on public network slices or isolated PLMNs, which could involve dependencies on public mobile network operators. The motivation was to enable industries like manufacturing, logistics, and utilities to deploy and operate their own 5G networks completely independently, with full control over security, performance, and user management. RSNPN as a concept solves the problem of unambiguous identification and access control for UEs within these autonomous networks.
It addresses limitations where earlier solutions for private access, such as Closed Access Groups (CAGs) for Non-Public Networks (NPNs) deployed with public network support, still required public network infrastructure. RSNPN facilitates a pure private network model, eliminating any reliance on a public PLMN for core network functions. This is essential for use cases requiring maximum isolation, data sovereignty, and tailored network characteristics. The creation of the RSNPN identifier formalizes the registration state, ensuring that mobility and session management procedures are correctly anchored to the private network's context, enabling reliable and secure industrial IoT and mission-critical communications.
Classification
Detected Changes Across Releases
from 3GPP Change RequestsSpecific changes extracted from the „Change history“ tables of 3GPP specifications (326 CRs across 5 releases). Complements the general historical overview above with the evidence-based evolution of this function.
In Release 15, the RSNPN (Registered SNPN) function was introduced, enabling a UE to be registered to a Standalone Non-Public Network. This allows the UE to access SNPN services via a PLMN by connecting to the 5GCN of the SNPN using the 3GPP access of the PLMN, and introduces specific registration types for SNPN onboarding and emergency services.
- Storing Configured NSSAI when the PLMN is changed TS 24.501CR0203
- Resolution of editor's note on equivalent PLMN list TS 24.501CR0141
- Resolution of editor's note on sub-states of state 5GMM-REGISTERED TS 24.501CR0145
- Clarification on SM congestion control specific to PLMN TS 24.501CR0154
- Interworking with E-UTRAN connected to EPC of a UE registered to 5GC via non-3GPP access TS 24.501CR0311
- Correct Extended Local Emergency Numbers List deletion upon PLMN change TS 24.501CR0274
+ 12 more changes
In Release 16, the RSNPN function was introduced, enabling a UE to access SNPN services via a PLMN's 3GPP access. This release defined new UE behaviors and network procedures, including specific handling for non-integrity protected messages and the introduction of an SNPN-specific attempt counter for non-3GPP access. It also clarified the support of network slicing and the handling of abnormal cases, such as de-registration, within an SNPN context.
- Serving PLMN rate control, general description TS 24.501CR0972
- Serving PLMN rate control, activation TS 24.501CR0973
- PLMN ID and NID provided to the lower layers TS 24.501CR1055
- Abnormal case handling for receipt of 5GMM cause value #11 from a PLMN TS 24.501CR1229
- Handling of non-integrity protected messages in an SNPN TS 24.501CR1453
- Serving network name in SNPN TS 24.501CR1511
+ 82 more changes
In Release 17, the RSNPN function was enhanced with new procedures for onboarding services, allowing a UE to perform an "initial registration for onboarding services in SNPN" to access provisioning services. This release defined specific slice handling for this onboarding process and introduced the state where a UE is "registered for onboarding services in SNPN," during which only onboarding services are available. Additionally, it specified mobility and deregistration procedures tailored for the SNPN onboarding scenario.
- SNN verification for SNPN supporting AAA-Server for primary authentication and authorization TS 24.501CR3137
- Enabling selection of an SNPN other than the subscribed SNPN TS 24.501CR3130
- "List of subscriber data" handling for SNPN supporting AAA-Server for primary authentication and authorization TS 24.501CR3133
- Support of the default configured NSSAI in the SNPN TS 24.501CR3260
- Onboarding in SNPN - slicing in initial registration TS 24.501CR3204
- Reject handling of registration for SNPN onboarding TS 24.501CR3319
+ 120 more changes
In Release 18, the RSNPN function was enhanced to support accessing SNPN services via non-3GPP access and to improve onboarding and localized services, including the provisioning of WLANSP information from a Registered SNPN. The release also introduced mechanisms for handling equivalent SNPNs for procedures like mobile identity selection and Unified Access Control (UAC), and allowed for a Credentials Holder (CH) controlled prioritized list of preferred SNPNs for accessing localized services.
- Providing registered SNPNs TS 24.501CR4835
- Equivalent SNPN usage for mobile identity selection TS 24.501CR4840
- Equivalent SNPN usage in UAC TS 24.501CR4841
- WLANSP provisioning in SNPN TS 24.501CR4936
- Support for UE accessing SNPN services using non-3GPP access TS 24.501CR4944
- The enhancement on onboarding services in SNPN supporting localized services TS 24.501CR5087
+ 70 more changes
In Release 19, enhancements for the Registered SNPN (RSNPN) function introduced specific procedures for localized services, including mechanisms for appropriate cell reselection and the maintenance of an FTA list for such services when using a GIN. The release also defined the handling of timers T3525 and T3540 in abnormal cases and for high-priority access, and clarified rules for the removal of memorized and forbidden SNPN lists upon timer expiry. Furthermore, it specified the recognition of an SNPN providing access for localized services and detailed the conditions for deleting forbidden PLMNs from the equivalent PLMN list during disaster roaming.
- Storage and replacement of RAT utilization control information associated to the current PLMN TS 24.501CR6460
- Information for ensuring appropriate cell reselection for localized services in SNPN TS 24.501CR6486
- T3525 abnormal case in SNPN TS 24.501CR6368
- Timer T3540 handling for causes triggering cell or PLMN selection TS 24.501CR6238
- Addition of a condition for the removal of memorized PLMN and SNPN Ids. TS 24.501CR6548
- Missing NOTE for T3540 for a UE with high priority access in selected PLMN or SNPN TS 24.501CR6546
+ 12 more changes
Explore further
Broader topics and technologies where RSNPN plays a role.
Defining Specifications
3GPP specifications that define or reference RSNPN, with the latest known release. Sourced from the 3GPP document catalog — see methodology.
| Specification | Title | Release |
|---|---|---|
| TS 24.501 vj50 | 5G NAS Protocols Specification | Rel-19 |