O-RAN specifications set the foundation for open, intelligent, virtualized, and interoperable Radio Access Networks (RAN). They describe different functions and interfaces of the O-RAN Architecture (Figure 1). O-RAN Work Groups (WG) and Focus Groups (FG), each covering different part of the solution, keep strong momentum in the specification development.
All O-RAN technical documents are available on our website at specifications.o-ran.org.
Since November 2024, O-RAN WGs and FGs published 67 technical documents, bringing the total to 130 titles in current version and 770 documents overall.
Five documents represent new titles:
This document specifies the capabilities exposed over E2 interface to enable efficient control of lower layers of the RAN, including collecting channel and traffic information and controlling the scheduling and precoding parameters. The main use case supported in this version is MU-MIMO Optimization.
The present document specifies the test methods for Indoor Pico Cell. It determines whether a WG7 White box hardware reference design conforms with its requirements as specified in its Hardware Architecture and Requirement specification (HAR). In the main body of this specification (in any “chapter”) the information contained therein is informative. It is noted that additional test cases may be required for a comprehensive testing, which will be considered in the future version of this document.
This document specifies the TE&IV APIs used to support TE&IV services within the SMO. This initial version collects:
The present document specifies the general aspects and principles of the Onboarding SMOS as described in the SMO Decomposition TR [i.3], clause 5.11. The specification identifies where the service fits into the Application Lifecycle as described in the OAM Architecture [i.5], clause 6. Beyond the general spects and principles, this document provides the use cases from the user perspective and specifies the service procedures, requirements, and information model for the service. This first version brings:
This document specifies the TE&IV Data Models used to support TE&IV services within the SMO.
This initial version collects:
The O-RAN Architecture Description document specifies the overall architecture of O-RAN. It describes all O-RAN architecture elements and relevant interfaces that connect them. This version introduces the SMOS (SMO Service), lists the SMOSs supported by the SMO and shows an example Non-RT RIC SMOF (SMO Function) comprising of rApps and A1 related SMOSs. The southbound interfaces of SMO are clarified for supporting FCAPs in both hierarchical and hybrid models. The RRM (Radio Resource Management) term is removed to ensure alignment with 3GPP. Finally, it clarifies that the O2 interface has deployment and infrastructure management services.
The SMO Intents-driven Management study (TR) introduces the exposure of the SMO services in a simplified form, RAN management via intents, to address the wide range of their applicability. This includes the various interactions within SMO management loops (closed, open), serving as a simplified method for management exposure of RAN services both externally and internally to other management or business systems. This version includes a use case for time-based intent deletion. A chapter structure for intent negotiation is added as the base for future works. Finally, editorial updates and text improvements are also incorporated.
This document describes potential O-RAN use cases at a very high level, emphasizing how the use case is enabled by the O-RAN architecture along with basic input data expectations and resulting actions. This version of O-RAN Use Cases Analysis Report includes enhancements to a use case (“Interference Optimization”), 3GPP Release-18 upgrade and some further editorial modifications for O-RAN ODR compliancy and ETSI PAS readiness.
This document describes selected O-RAN use cases in further details to facilitate relevant O-RAN Work Groups to define requirements for associated O-RAN functions and interfaces. This version of O-RAN Use Cases Detailed Specification Report includes new sub use case additions to Shared O-RU use case, enhancements to a use case (“Interference Optimization”, 3GPP Release-18 upgrade and some further editorial modifications for O-RAN ODR compliancy and ETSI PAS readiness.
This document describes O-RAN slicing related use cases, requirements and architecture. Along with requirements and a reference slicing architecture, slicing related impact to O-RAN functions and interfaces is also captured. This version of O-RAN Slicing Architecture Technical Specification includes addition of slice subnet feasibility and reservation procedure, 3GPP Release-18 upgrade and some further editorial modifications for O-RAN ODR compliancy and ETSI PAS readiness.
This document specifies the general aspects and principles of the A1 interface. This version brings updated A1 service architecture, and A1 ML functions and related procedures.
This document describes the transport protocol of the O-RAN A1 interface. This version brings Editorial enhancement of references.
This document specifies the application protocol of the A1 interface. This version brings an update to the general referencing and A1 service architecture.
This document specifies test cases for conformance testing and interoperability testing of the Non-RT RIC and the Near-RT RIC over the A1 interface. This version brings editorial enhancements of references.
The O-RAN R1GAP Specification summarizes the R1 interface specification objectives and specifies the principles and procedures related to the O-RAN R1 interface. In this version, the specification has been updated by adding the A1 ML model management services, procedure to query of AI/Ml model training capabilities , procedure to retrieve the status of the data request and data subscription and updated the existing procedures for service registration and authorization service.
This document specifies the Type Definitions for R1 Services. It is part of a TS-family covering the R1 interface specifications. This release includes the new DME type for RAN OAM Trace Metrics.
This document specifies test cases for conformance testing and interoperability testing of the rApps and R1 services over R1 interface. This release includes the conformance test of Non-RT RIC as DUT for Service registration test case.
This document describes use cases and requirements for the O-RAN R1 interface. This version adds use cases for AIML inference capability information Query.
This document contains a realization for the procedures identified in O-RAN R1 interface: General Aspects and Principles. This version updated the specification by migration of all API’s from Release 17 to Release 18 of 3GPP, updated the A1 Policy management API and Model discovery API and moved the same to release version, updated the Data registration API, Data access API and Data offer API by removing the consumerId from the uri structure.
This specification defines the data types for A1 Policies and A1 Enrichment Information in a reusable and extensible way. It allows new policy types to be created independently of the generic application protocol parts. This version updates to the common schema and the policy and EI types related to that. There are updated references.
This document describes use cases for the O-RAN A1 interface. This version brings Use cases for Authorization of service access requests and AI/ML model training.
This document describes O-RAN WG2 Non-RT RIC use cases in detail including the required datasets, the flows, and the interactions within and outside of Non-RT RIC with other O-RAN components. As a result of the use case analysis, this specification captures the requirements imposed by these use cases on the Non-RT RIC architecture, A1 and R1 interfaces as well. Main updates for this version are:
E2 General Aspects and Principles (E2GAP) provides a stage 2 description of the E2 interface between Near-RT RIC and an E2 Node. This version includes support for new features E2 Resource Status, RIC Subscription State Control, RIC Assistance and Service Level error handling. It also implements changes related to the liaison statement received from ETSI MSG after approval of the ETSI PAS version of the O-RAN E2GAP specification.
E2 Application Protocol (E2AP) provides a stage 3 description of the E2 interface between Near-RT RIC and an E2 Node. This version includes support for new features RIC Subscription State Control, RIC Assistance and Service Level error handling. It also implements changes related to the liaison statement received from ETSI MSG after approval of the ETSI PAS version of the O-RAN E2AP specification.
E2 Service Model (E2SM) provides describes the O-RAN specified RAN Function-specific Service Models supported over E2 (E2SM) and specifies the common elements for use in E2 service models. This version includes support for new features RIC Assistance and Service Level error handling. It also implements changes related to the liaison statement received from ETSI MSG after approval of the ETSI PAS version of the O-RAN E2SM specification.
This document specifies the capabilities exposed over E2 interface to enable efficient control of lower layers of the RAN, including collecting channel and traffic information and controlling the scheduling and precoding parameters. The main use case supported in this version is MU-MIMO Optimization.
E2 Service Model KPM (E2SM-KPM) provides RAN Function-specific Service Models of KPM (Key Performance Measurement) for use in xApps. This version of E2SM-KPM specification includes addition of DL and UL Transmitted Data Volume for MAC SDU. It also implements editorial changes and update of the revision history.
This document specifies the E2 Service Model (E2SM) to enable exposure of services for node and cell level configuration and control over the E2 interface. This version of E2SM-CCC specification includes addition of RIC Query services, cell DTX/DRX configuration, performance objective parameters to O-NESPolicy, O-RU capability reporting for user plane configuration and ASM and RF Channel Reconfiguration and editorial updates for O-RAN Drafting Rule (ODR) alignment.
This document specifies the E2 Service Model (E2SM) for UE and Cell level services over E2 interface. This version of E2SM-RC includes support for Massive MIMO and Grid of Beam Forming features, addition of failure reporting at E2SM service level along with some editorial fixes.
The O-RAN Near-RT RIC Architecture document specifies the Near-RT RIC internal architecture and functionalities, and the stage 2 definitions of Near-RT RIC APIs. This version includes new Near-RT RIC API stage 2 definitions for AI/ML model management and exposure, E2 query, E2 subscription modification, and conflict mitigation. It also includes improvements, clarifications and corrections concerning terms, requirements, A1 Policy service description, etc., as well as an informative description for xApp’s workflow.
This document details the functional and non-functional requirements on Near-RT RIC and E2 interface from the O-RAN use cases under study in O-RAN WG3. This version of WG3 Use Case Requirements specification includes enhancements to use cases (DMRS optimization and PRB blanking) and editorial updates for O-RAN Drafting Rule (ODR) alignment.
This document specifies the control plane, user plane and synchronization plane protocols used over the fronthaul interface. The summary of updates for this version is below:
This document defines tests that validate the conformance to the protocols defined for the Lower Layer Split Option 7.2x interface between the O-RU and the O-DU. This version brings:
This specification defines the Management Plane for the O-RAN Open Fronthaul based on the selected lower-layer split point as defined within the Open Fronthaul Control Plane, User Plane and Synchronization Plane specification. The summary of updates for this version is below.
The scope of C-Plane profile spec is to further clarify (i.e. profile) for each RAN node the expected behavior (still within the scope of the 3GPP specifications). E.g., Usage of IEs for each use case, general behavior of each node, etc. C-Plane profile spec contains profiles of X2/F1/Xn C-Plane procedure for EN-DC use cases, NR-SA use cases and NR-DC use cases. This version brings:
The scope of WG5 IOT spec is to specify interoperability tests for RAN Node from different vendors implemented in accordance to the WG5 C-plane and U-plane profiles in the specification WG5.C.1. and WG5.U.0, respectively. This version captured 12 new test cases for C-plane profile.
This document introduces and examines different scenarios and use cases for O-RAN deployments of Network Functionality into Cloud Platforms, O-RAN Cloudified NFs and O-RAN Physical NFs. This version clarifies terminology for transport network (i.e. networks to which the O-Cloud is attached)
This document specifies a test specification for test and validation of the O-Cloud interfaces/APIs. This version includes refinements to the test cases for the O2 DMS ETSI profile.
This specification defines O-RAN O-Cloud functions and protocols for the O-RAN O2 interface. This version clarifies the network to which O-Cloud connects.
The O-Cloud Information Model provides the logical model of information elements and their relationships. This release introduces additional namespaces which are required to introduce O-Cloud provisioning to the O2 IMS Interface
This document provides O-Cloud IoT specification, and includes definition of the interoperability testing methodology and a set of tests for the O-Cloud Notification API. This version consists of the updates for the introduction, testing methodology, references and diagrams to focus on WG6 O2 specifications and the interfaces specified by WG6.
This specification defines O-RAN O-Cloud IMS interface functions and protocols for the O-RAN O2 interface. This release introduces support for additional FM and PM stage 3 APIs as well as removing the now obsolete information model.
This specification defines O-RAN O-Cloud hardware accelerator interface functions and protocols for the O-RAN AAL interface. This release introduces the declarative approach for control and management interface for the AAL. It also introduces the concept of by pass functions for accelerated functions. Finally there are updates to the AAL FFT Profile and some editorial updates.
This document specifies how to accelerate the High-PHY functionality of an O-DU where the High-PHY Acceleration Function (AF) is hosted on an AAL-LPU that is assigned to the AAL Application that is part of the O-DU. This document also specifies a set of AAL Profiles and procedures for utilizing the AALI Common Management (AALI-C-Mgmt) and Application (AALI-C-App) interfaces to convey the information elements specified by the AAL Profiles. This release introduces additional parameters for LDPC decoding in PUSCH Data parameters.
This document introduces different use cases for O-RAN orchestration of virtualized RAN and the interfaces used for management and orchestration, in particular the O1 interface between the service management and orchestration framework and the RAN managed functions and the O2 interface between the service management and orchestration framework and the O-Cloud Infrastructure Management Services/Deployment Management Services that controls resource assignment for Virtualized Network Functions. This version incorporates a number of terminology changes for alignment within WG6 and for clarification, plus new use cases for O-Cloud Node Cluster creation/update using O-Cloud template.
The present document specifies the test methods for Indoor Pico Cell. It determines whether a WG7 White box hardware reference design conforms with its requirements as specified in its Hardware Architecture and Requirement specification (HAR). In the main body of this specification (in any “chapter”) the information contained therein is informative. It is noted that additional test cases may be required for a comprehensive testing, which will be considered in the future version of this document.
This specification defines the O-CU and O-DU software architecture, functional blocks, and API definitions. This version brings:
This specification defines interoperability test cases for O-CU and O-DU. This version adds 2 new test cases on network energy savings.
This document is intended to describe best practices for O-RAN xhaul transport based on WDM technology. Version 5.0 enhanced the scope of this work item from Fronthaul to Xhaul which includes Midhaul and Backhaul. It also added content on MOPA and beyond 25G optics.
The document is intended to describe best practices for O-RAN Architecture and Solution for X-haul timing 3 & synchronization. Version 6.0 includes Yang data model for End-to-end Sync monitoring framework using Telemetry streaming in Annex H.
This document defines the testing requirements for an Open Xhaul transport infrastructure. Version 5.0 Added WDM test cases, updated Inclusive Terminology in synchronization section
This document specifies management services for the O-RAN O1 interface and includes requirements, notifications and protocols. Summary of the changes since the previous version:
The O-RAN OAM Architecture identifies management services, functions and interfaces supported in O-RAN, including the interworking between SMO and O-RAN O-Cloud components. Requirements are derived from end-to-end OAM use cases, including the initial provisioning of O-RAN service across VNFs and PNFs and the collection of measurement data. Summary of the changes since the previous version:
The O-RAN Information Model and Data Models document specifies the Information Model and the Data Models that are foundational for O-RAN’s model-driven architecture and for the functions carried out over O-RAN interfaces. Summary of the changes since the previous version:
The present document specifies the O-RAN Performance Measurements (PMeas) for 5G networks that may be supported on the O1 Interface. This version brings:
This document specifies the Information Model used to support TE&IV services within the SMO. The TE&IV Information Models described in this document are structured using the concept of Namespaces. In addition, relevant sections in this document include information imported from existing standards and industry work that serve as a basis for O-RAN TE&IV. Summary of the changes since the previous version:
This document specifies the TE&IV APIs used to support TE&IV services within the SMO. This initial version collects:
The present document specifies the general aspects and principles of the Onboarding SMOS as described in the SMO Decomposition TR [i.3], clause 5.11. The specification identifies where the service fits into the Application Lifecycle as described in the OAM Architecture [i.5], clause 6. Beyond the general spects and principles, this document provides the use cases from the user perspective and specifies the service procedures, requirements, and information model for the service. This first version brings:
This document specifies the TE&IV Data Models used to support TE&IV services within the SMO.
This initial version collects:
The present document specifies the Information Model and the Data Model for Network Resource Model (NRM) that are foundational for functions carried out over the O-RAN O1 interface. Main updates of this version:
This Technical Specification contains security requirements and controls for O-RAN architecture element, O-RAN defined interfaces as well as transversal security requirements and controls for the O-RAN architecture. The Version 11.00 of the technical specification includes key updates such as new security requirements for AI/ML, access to the O-Cloud platform, MACsec for S-plane and MACsec ciphers, U-Plane authentication and authorization, and reformulated app package validation procedures. It also updates O1 and O2 security requirements. Additional requirements have been added for the certificate management framework clause and API security, along with two new annexes mapping security requirements and controls, and summarizing O-RAN Security Controls. Enhancements also cover Y1 security controls, Near-RT RIC and A1 security requirements, SBOM, O-Cloud certificate management, security descriptor updates, enforcement of security policies by the O-Cloud, and protection against side-channel attacks on the O-Cloud secure environment.
This document provides security protocol specifications for an O-RAN compliant implementation. Version 11 introduces rewritten TLS general requirements and NetConf clauses, and removes alpha status from the OAuth2.0 Access Token API Open API specification. Additionally, editorial references have been updated for clarity, consistency and ODR conformance.
These specifications validate the proper implementation of security requirements and protocols, emulate security attacks, and validate the effectiveness of security mitigation methods. Version 9 does not add any new test cases. As a result of review, some test cases were removed and some test cases were slightly changed. Many smaller editorial changes were incorporated in order to have same format of all test cases. Changes affected clauses 6, 7, 8, 9, 11.1, 14, 18.4, 19.2 and 24. Some test cases were removed from clauses 6, 8 and 9.
The O-RAN Security Threat Modeling and Risk Assessment TR identifies the assets at risk and outlines potential security threats to the O-RAN system, along with guiding security principles to mitigate these risks. It further assesses the likelihood and potential impact of these identified threats on the O-RAN system. The TR has been updated to Version 5, incorporating several improvements over Version 4:
The Fronthaul CUS-Plane Security Technical Report examines the security aspects of the CUS-Plane on the Open Fronthaul interface between the O-DU and O-RU. It identifies critical assets, key issues, threats, and potential risks, and proposes security requirements and solutions to effectively secure CUS-Plane traffic. Thev03.00 of the technical report has been updated with several changes, including updates to the security analysis of the C-plane, the inclusion of MACsec for S-Plane, and revisions to clause 4.6 for better alignment with deployment considerations for MACsec. Additionally, MACsec for Shared O-RU configuration has been added, and the deployment considerations for MACsec also include Shared O-RU scenarios.
This technical report studies the applicability of a Zero Trust Architecture (ZTA) to the O-RAN Architecture. It identifies assets and security controls in pursuit of a ZTA while considering those already existing in WG11 specifications. The second version of the ZTA technical report adds the gap analysis comparing current security requirements and controls of O-RAN assets to the ZTA security guidelines derived from CISA’s Zero Trust Maturity Model.
This technical report is the result of a study on the use of centralized user management on the O-RU. The report contains identified key issues, threats and proposed mitigations. This version contains editorial changes and updates to improve readability only.
OAuth2.0 version 4.0 consists of O-RAN assets and additional security threats for OAuth2.0. Provided new two solutions related to OAuth profile and RBAC.
This technical report studies a comprehensive framework for certificate management across the O-RAN environment. CMF version 4.0 comprises conclusion for Solution #15, solutions based on alarms, and editorial changes to better align with ETSI PAS requirements.
This technical report provides the threat model and risk assessment for AI/ML in O-RAN. The report identifies threats and risks and recommends potential security controls to protect against those threats through safeguards or mitigations. This version of the TR contains adaptations to wording and naming used in the Threat Model and Risk Assessment TR, and technical corrections to one threat description. Additionally, editorial references have been updated for clarity, consistency and ODR conformance.
This technical report documents a security analysis for the SMO. The TR provides assets, threats, risk scoring, and recommended security controls across 3 threat groups: SMO, O2 interface, and External Interfaces. Threat analysis is based upon the STRIDE model and risk scoring is based upon likelihood and impact. Recommended security controls were used to form normative SMO security requirements.
This version of the TR provides updates for Decoupled SMO. Further security analysis of Decoupled SMO is pending for upcoming release trains.
TR Circular economy guidelines on network equipment defines circular economy criteria aspects and indicators applicable on network equipment such as: O-CU, O-DU and O-RU, based on the recommendation ITU-T L.1023 (08/2023) “Assessment method for circularity performance scoring” with the intention of reducing environmental impact through the homogenization and prioritization of said criteria according to their impact on the contribution to the circular economy model. This version of document brings editorial improvements.
