Description
Originating Identification presentation Restriction (OIR) is a supplementary service standardized by 3GPP that provides the calling party with the ability to prevent their identification information (typically the Calling Party Number or SIP URI) from being presented to the called party. The service operates within the call control and session management layers of the network, intercepting and modifying the signaling messages that carry caller identification. When a user activates OIR (either per-call via a prefix or as a permanent subscription service), the network applies logic to either remove the identification from the outgoing signaling or mark it as 'presentation restricted'. This is enforced at the originating network's control nodes, such as the MSC (Mobile Switching Centre) in circuit-switched networks or the S-CSCF (Serving Call Session Control Function) in IMS (IP Multimedia Subsystem) networks. The service interacts with the HSS (Home Subscriber Server) or HLR (Home Location Register) to verify subscription data and service authorization. In the IMS architecture, OIR is implemented as an originating service within the S-CSCF, utilizing Initial Filter Criteria (iFC) to trigger the appropriate Application Server if needed for advanced logic. The restriction can be overridden in specific cases, such as emergency calls or calls to certain authorized numbers, as defined by network policy and regulatory requirements. The called party's network may also apply complementary services like Connected Line Identification Presentation (COLP) or generate privacy indicators based on the received restricted status.
Purpose & Motivation
OIR was created to address growing user privacy concerns, allowing individuals to control the disclosure of their personal contact information. Before such services, caller identification was typically always presented, which could lead to unwanted contact, harassment, or privacy breaches. The service solves the problem of involuntary information disclosure in telephony, giving subscribers autonomy over their identity. Its introduction was motivated by regulatory requirements in many regions mandating privacy options for telecommunications users. It also enables business applications, such as allowing employees to make business calls without revealing personal mobile numbers. The service provides a standardized mechanism across different network generations (circuit-switched and packet-switched/IMS), ensuring consistent privacy functionality as networks evolved.
Key Features
- Allows calling users to restrict presentation of their CLI (Calling Line Identity) or SIP URI
- Can be invoked per-call using a prefix (e.g., *67) or as a permanent subscription service
- Integrated into both circuit-switched (CS) and IMS-based call control architectures
- Interacts with subscriber databases (HLR/HSS) for service authorization
- Can be overridden for emergency services and other priority calls as per network policy
- Generates appropriate privacy indicators in signaling (e.g., 'presentation restricted' parameter)
Evolution Across Releases
Introduced OIR as a standardized supplementary service within the IMS framework, defining its interaction with SIP signaling. Initial architecture integrated it into the S-CSCF service logic and defined the 'privacy' header and P-Asserted-Identity handling for IMS sessions.
Enhanced interworking between CS and IMS domains for OIR, ensuring consistent privacy when calls traverse different network types. Updated specifications for E-UTRAN/EPC integration.
Further refinements to IMS service continuity procedures involving OIR during handovers between CS and IMS. Clarifications on interaction with other supplementary services.
Minor updates and corrections to OIR procedures as part of broader IMS and LTE enhancements. Alignment with SRVCC (Single Radio Voice Call Continuity) specifications.
Continued maintenance and clarifications in OIR specifications, ensuring compatibility with new IMS features and network deployments.
Updates related to IMS evolution and support for new service scenarios. Enhanced details on OIR interaction with VoLTE (Voice over LTE).
Incorporated OIR considerations for Mission Critical Push-to-Talk (MCPTT) services, where privacy might be managed differently for public safety communications.
Maintenance updates and alignment with ongoing 5G and IMS standardization work. No major functional changes to core OIR service.
Ensured OIR service continuity and compatibility in the 5G System (5GS) architecture, particularly for voice services over 5G (VoNR). Defined interactions with 5GC network functions.
Further integration of OIR within the 5G ecosystem, including support for network slicing scenarios that might impact service triggering and policy enforcement.
Maintenance and potential enhancements for edge computing and non-public network deployments, ensuring OIR functions correctly in distributed architectures.
Continued evolution as part of 5G-Advanced, with focus on service robustness and potential integration with advanced AI/ML-based privacy features (under study).
Ongoing maintenance and updates to ensure OIR remains effective and secure within the evolving 3GPP architecture, addressing any new signaling or security requirements.
Projected maintenance and potential enhancements aligned with future 3GPP releases, ensuring the service's longevity and relevance.
Defining Specifications
| Specification | Title |
|---|---|
| TS 22.173 | 3GPP TS 22.173 |
| TS 22.273 | 3GPP TS 22.273 |
| TS 22.401 | 3GPP TS 22.401 |
| TS 24.173 | 3GPP TS 24.173 |
| TS 24.186 | 3GPP TS 24.186 |
| TS 24.196 | 3GPP TS 24.196 |
| TS 24.292 | 3GPP TS 24.292 |
| TS 24.404 | 3GPP TS 24.404 |
| TS 24.405 | 3GPP TS 24.405 |
| TS 24.406 | 3GPP TS 24.406 |
| TS 24.407 | 3GPP TS 24.407 |
| TS 24.408 | 3GPP TS 24.408 |
| TS 24.410 | 3GPP TS 24.410 |
| TS 24.411 | 3GPP TS 24.411 |
| TS 24.416 | 3GPP TS 24.416 |
| TS 24.417 | 3GPP TS 24.417 |
| TS 24.429 | 3GPP TS 24.429 |
| TS 24.447 | 3GPP TS 24.447 |
| TS 24.454 | 3GPP TS 24.454 |
| TS 24.504 | 3GPP TS 24.504 |
| TS 24.505 | 3GPP TS 24.505 |
| TS 24.508 | 3GPP TS 24.508 |
| TS 24.516 | 3GPP TS 24.516 |
| TS 24.529 | 3GPP TS 24.529 |
| TS 24.604 | 3GPP TS 24.604 |
| TS 24.605 | 3GPP TS 24.605 |
| TS 24.606 | 3GPP TS 24.606 |
| TS 24.607 | 3GPP TS 24.607 |
| TS 24.608 | 3GPP TS 24.608 |
| TS 24.610 | 3GPP TS 24.610 |
| TS 24.611 | 3GPP TS 24.611 |
| TS 24.615 | 3GPP TS 24.615 |
| TS 24.616 | 3GPP TS 24.616 |
| TS 24.629 | 3GPP TS 24.629 |
| TS 24.642 | 3GPP TS 24.642 |
| TS 24.647 | 3GPP TS 24.647 |
| TS 24.654 | 3GPP TS 24.654 |
| TS 29.163 | 3GPP TS 29.163 |
| TS 29.165 | 3GPP TS 29.165 |
| TS 29.292 | 3GPP TS 29.292 |
| TS 29.364 | 3GPP TS 29.364 |
| TS 29.864 | 3GPP TS 29.864 |
| TS 32.275 | 3GPP TR 32.275 |
| TS 32.850 | 3GPP TR 32.850 |