Description
Restricted Local Operator Services (RLOS) is a service control mechanism defined within the 3GPP architecture, primarily managed by the Home Subscriber Server (HSS) and applied through the Policy and Charging Control (PCC) framework. The core function of RLOS is to impose a specific service profile on a user's session, which selectively permits only a predefined set of services deemed essential or locally relevant by the network operator. When a user is flagged for RLOS, the HSS provides an indication to the serving network nodes, such as the MME in EPS or the AMF in 5GS. This indication triggers the enforcement of a corresponding PCC rule set, which is configured to allow only certain traffic flow templates (TFTs). Typically, these permitted TFTs are for accessing the operator's own service network (e.g., for customer care, balance top-up, or service portals) and for emergency services (e.g., calls to 112, 911). All other outgoing communication attempts, such as regular voice calls or data sessions to the public internet, are blocked by the Policy and Charging Enforcement Function (PCEF) or the Session Management Function (SMF) with UPF. The architecture integrates with the Rx and Gx interfaces (or their 5GC equivalents) to dynamically apply these policies. RLOS is not a standalone network function but a service logic implemented across core network elements, leveraging existing subscription data and policy control mechanisms to achieve granular service restriction. Its role is to provide a flexible tool for operators to manage service accessibility in a controlled manner, aligning with commercial, regulatory, or network management needs without requiring complete service disconnection.
Purpose & Motivation
RLOS was introduced to address specific operational and commercial scenarios where a subscriber needs to be restricted from making general outgoing calls but must retain access to a minimal set of operator-managed services. A primary use case is for inbound roamers who have not established a roaming agreement or whose credit has been exhausted; instead of denying all service, the operator can apply RLOS to allow the user to contact customer service for assistance or to top up their account. It also serves users on restrictive service plans, ensuring they can always reach emergency services and operator support. Historically, without such a feature, the options were binary: either full service access or complete service barring. RLOS provides a middle ground, enhancing customer experience by maintaining a lifeline to essential services while protecting the operator from potential revenue loss from unpaid usage. Its creation was motivated by the need for more sophisticated service control within the PCC architecture defined from Release 7 onwards, allowing for dynamic, policy-driven service differentiation beyond simple barring lists.
Detected Changes Across Releases
from 3GPP Change RequestsSpecific changes extracted from the „Change history“ tables of 3GPP specifications (110 CRs across 5 releases). Complements the general historical overview above with the evidence-based evolution of this function.
In Release 15, the RLOS function was enhanced with the introduction and management of extended local emergency numbers, including their storage and correct deletion upon a PLMN change. It also added the encoding of characters for associated emergency service URNs and clarified the applicable domain for initiating calls using these numbers. Furthermore, support was introduced for attempting EPS Attach specifically for Emergency Bearer Services.
- Addition of NAS indication for dual connectivity with NR being restricted TS 24.301CR2893
- Extended and local emergency numbers and applicable domain for call initiation TS 24.301CR3012
- Storage of extended local emergency numbers TS 24.301CR3013
- Support for volume based charging of IMS services TS 29.214CR1614
- 3GPP PS Data Off - update to services for roaming TS 31.102CR0784
- Mission Critical Services configuration data update to USIM TS 31.102CR0808
+ 10 more changes
In Release 16, the 3GPP standards introduced the Restricted Local Operator Services (RLOS) function, defining new procedures for UEs to attach specifically for RLOS access. This included detailed specifications for the PDN connectivity procedure, default EPS bearer context activation, and distinct handling for mobility, service requests, and NAS security mode control for RLOS-attached UEs. The release also defined specific EMM substates, service restrictions, and exception cases for this new attachment type.
- Support for Restricted Local Operator Services in EPC TS 23.401CR3491
- Support of restricted local operator services TS 24.301CR3160
- Restricted local operator services request indication TS 24.301CR3161
- Authentication and security handling for restricted local operator services TS 24.301CR3162
- PDN connectivity procedure for RLOS attached UEs TS 24.301CR3163
- Attached for access to RLOS TS 24.301CR3177
+ 49 more changes
In Release 17, enhancements for Restricted Local Operator Services (RLOS) included introducing a specific EMM cause for "UAS services not allowed" in EPS NAS messaging and refining procedures for paging restriction on specific EPS bearers. The release also corrected and improved RLOS definitions and handling, such as enabling E-UTRA capability triggered by an RLOS call and clarifying the local detach procedure before entering the EMM-DEREGISTERED state.
- PDN connections associated with the EPS bearer identities for which paging is restricted TS 24.301CR3548
- UAS services not allowed indication in EPS NAS message TS 24.301CR3618
- Local deactivation of UP resource for an MA PDU session with PDN leg - 24301 Part TS 24.301CR3657
- Update on the UAS services for ePCO support TS 29.274CR2052
- 5G ProSe configuration related services and files TS 31.102CR0929
- Support of PC5 DRX configuration policies and NR-PC5 unicast security policies for V2X services TS 31.102CR0953
+ 10 more changes
In Release 18, enhancements for RLOS included a correction to the condition for triggering a Tracking Area Update procedure for the local release of a PDN connection. Furthermore, clarifications were provided on the handling of Operator Defined QoS Class Identifiers during inter-PLMN handover scenarios.
- Support DC in 3GPP PS Data Off exempt services TS 31.102CR1054
- Support of Uu MBS configuration and AS MBS configuration policies for V2X services TS 31.102CR1023
- Clarification on the handling of Operator defined QCIs at inter-PLMN Handover TS 23.401CR3740
- Correction to condition to trigger TAU for local release of PDN connection TS 24.301CR3769
- When MME does not support ePCO for non-IP/ethernet/UAS services TS 24.301CR3914
- Handling authentication reject during emergency services TS 24.301CR3962
+ 2 more changes
In Release 19, the RLOS function was enhanced with new mechanisms for managing disaster roaming services, including a PLMN-specific attempt counter for UEs attached under these conditions and rules to preserve Forbidden PLMN lists upon timer expiry. It also introduced the "Operator-controlled-LSP-PLMN" parameter with an associated "PeriodicSearchTimerNonLSP" for network control. Furthermore, the release defined new UE detach triggers and clarified procedures for maintaining emergency bearer services after a disaster condition ends.
- Deletion of forbidden PLMNs from list of equivalent PMNs when UE is attached for disaster roaming services TS 24.301CR4566
- PLMN-specific attempt counter for the UE attached for the disaster roaming services TS 24.301CR4567
- UE attached for disaster roaming services doesn't delete FPLMN lists when timer T3245 expires TS 24.301CR4569
- MME behaviour when the disaster condition has ended and the UE maintains a PDN connection for emergency bearer services TS 24.301CR4572
- Introducing Operator-controlled-LSP-PLMN and PeriodicSearchTimerNonLSP TS 31.102CR1081
- IMS emergency services in eCALL-INACTIVE state TS 24.301CR4164
+ 9 more changes
Explore further
Broader topics and technologies where RLOS plays a role.
Defining Specifications
3GPP specifications that define or reference RLOS, with the latest known release. Sourced from the 3GPP document catalog — see methodology.
| Specification | Title | Release |
|---|---|---|
| TS 23.203 vj20 | Policy and charging control architecture | Rel-19 |
| TS 23.221 vj00 | 3GPP System Architectural Requirements | Rel-19 |
| TS 23.401 vj50 | Evolved Packet System (EPS) Stage 2 Description | Rel-19 |
| TR 23.715 vg00 | Study on access to restricted local operator services | Rel-16 |
| TS 24.229 vj50 | IMS call control protocol based on SIP and SDP | Rel-19 |
| TS 24.301 vj60 | NAS protocol for Evolved Packet System | Rel-19 |
| TS 24.368 vj40 | NAS Configuration Management Object | Rel-19 |
| TS 29.165 vj10 | Inter-IMS Network to Network Interface (NNI) | Rel-19 |
| TS 29.212 vj00 | Gx/Gxx/Sd/St Diameter Protocol | Rel-19 |
| TS 29.213 vj20 | PCC Signalling Flows and QoS Mapping | Rel-19 |
| TS 29.214 vj20 | Policy and Charging Control over Rx | Rel-19 |
| TS 29.274 vj50 | GTPv2-C Control Plane Protocol Specification | Rel-19 |
| TS 31.102 vj40 | USIM Application Specification | Rel-19 |
| TS 33.401 vj10 | EPS Security Architecture | Rel-19 |
| TS 33.815 vg01 | Security Study for PARLOS/RLOS | Rel-16 |
| TS 36.331 vj00 | LTE RRC Protocol Specification | Rel-19 |