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) or Focus Groups (FG), each covering different part of the solution, keep strong momentum in specification development.
Since March 2023, O-RAN WGs and FGs published 57 technical documents, bringing the total to 101 specification titles in 438 versions.
Four documents represent new titles:
All released O-RAN ALLIANCE specifications, including the recent ones published in July 2023, are available for download on our website.
The O-RAN Architecture Description document specifies the overall architecture of O-RAN. It describes all of the O-RAN functions and relevant interfaces that connect these functions. This version elucidates the role of Y1 consumers within or outside the PLMN trust domain for consuming Y1 services produced by the Near-RT RIC. It further clarifies that the Y1 consumers box depicted in the figures does not denote a logical O-RAN function. In addition to Y1 interface and Y1 consumers, the definitions of SMO External Interface, SMO External System, SMO Functions (SMOFs), and SMO Service (SMOS) have been added. Finally, the description of O-DU has been enhanced to align it with gNB-DU of 3GPP.
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 includes additional content related to exposure of slice management capabilities for multi-Operator use cases.
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 includes a new use case “Industrial vision SLA assurance” and minor updates to some of the existing use cases.
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 includes updates to two use cases “Shared O-RU” and “Multi-vendor Slices”, as well as some editorial updates.
This Technical Report defines overall use cases for Network Energy Savings. The TR v02.00 includes additional use cases, Advanced Sleep Mode Selection and O-Cloud Resource Energy Saving Mode on top of Carrier and Cell Switch Off/On and RF Channel Reconfiguration Off/On released in v1.00.
This document describes use cases for the O-RAN A1 interface. This version is aligned with the latest O-RAN TS template. O-RAN drafting rules compliance and ETSI PAS submission requirements will be addressed in the next release.
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 brings editorial enhancement.
This document provides the technical specification for the Non-Real-Time RAN Intelligent Controller (Non-RT RIC) architecture. This version introduces the AI/ML workflow services and functions, as well as rApp management services. In addition, RAN OAM-related services and functions are added to replace the O1 related services and functions.
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 O1-related services was updated as RAN OAM related services, the procedure of update and de-registration of rApp registration services was updated as part of SME, and finally, the O2-deployment management services was updated.
This document describes use cases and requirements for the O-RAN R1 interface. This version of specification introduced the RAN OAM related use cases for read configuration and CM get schema, updated the query information for Query performance use case, and added the R1 security requirements to the R1 interface requirements.
This document describes transport protocols for the O-RAN R1 interface services. In this version of Specification references of R1 Security protocol requirements was updated as specified in WG11 specifications (Security requirements Specifications and Security protocol specifications). It also removed the duplicated text of the Security requirements in the R1 Transport protocol.
This new spec provides the API structure for the SME. It also covers the Service registration and discovery. This Version of R1 Application protocols added the versioning of the API’s and Versioning of the Open API’s and this spec also added the API structure for the SME (Service registration and service discovery).
This document (E2GAP) together with (E2AP) describes the general architecture of Near-RT RIC and the main functions and procedures supported over the E2 interface, and the E2 application protocol of Near-RT RIC. This version of the specification introduces changes that ensure compliance with O-RAN drafting rules and ETSI PAS submission requirements.
This document (E2AP) together with (E2GAP) describes the general architecture of Near-RT RIC and the main functions and procedures supported over the E2 interface, and the E2 application protocol of Near-RT RIC. This version of the specification introduces changes that ensure compliance with O-RAN drafting rules and ETSI PAS submission requirements.
This document serves as the overall framework for the set of specialized E2SMs, each of which is dedicated to a specific RAN function. This document also includes the common information elements used across the specialized E2SMs. This version of the specification introduces changes that ensure compliance with O-RAN drafting rules and ETSI PAS submission requirements
This document specifies the control plane, user plane and synchronization plane protocols used over the fronthaul interface. This version brings the following feature introductions/modifications of functionalities:
Additional clarifications:
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. This version brings the following new functionalities:
Bug fixes and correction to v11.00:
This document specifies the interoperability testing (IOT) for O-DU and O-RU from different vendors connected using the O-RAN fronthaul (FH) interface. This version brings new capabilities, including:
This document defines tests that validate the conformance to the protocols defined for the Lower Layer
Split interface between the O-RU and the O-DU. This version provides the following M-Plane Test additions and corrections:
This specification describes the Cooperative Transport Interface (CTI) and related message protocol when the fronthaul between the O-DU and O-RU is realized via a resource allocation-based transport network. This version brings several updates.
Editorial: conforming to TSC document drafting rules, including:
Clarifications of existing mechanisms and terms, including:
This document describes the Transport Management Procedures for the Cooperative Transport Interface (CTI). This version brings several updates.
Editorial: conforming to TSC document drafting rules, including:
Completion and update of Information Model for CTI Client in O-DU, including:
Completion and update of Data Model for CTI Client in O-DU:
The scope of O1 interface for O-DU spec is to describe the supported management features including “start-up” installation, PNF software management, provisioning management, performance management, fault management and file management towards the O-DU via O1 interface. This spec also includes O-DU related performance counters, information models, and data models.
This version of the specification adds:
The scope of O1 interface for O-CU spec is to describe the supported management features including “start-up” installation, PNF software management, provisioning management, performance management, fault management and file management towards the O-CU-CP and O-CU-UP via O1 interface. This spec also includes O-CU related performance counters and information models.
This version of the specification adds:
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.
Main Updates compared to v06.00
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.
Main Updates compared to v09.00
This specification outlines the general aspects and principles of the O2 interface. This version adds IMS Provisioning Concepts.
This specification outlines the general aspects and principles of the O2 interface. This version adds PM Information Model.
This specification outlines the deployment management services of the O2dms interface profile based on Kubernetes Native API for containerized NFs. This version adds Healing.
This specification outlines the deployment management services of the O2dms interface profile based on ETSI NFV protocol and data models. This version adds AAL Mapping.
This document contains use cases for O-RAN orchestration of virtualized RAN and the associated requirements on interfaces used for management and orchestration. This version adds 15 new updated use cases.
This document contains the initial release of the description of Tests for O-Cloud Notification API, O2 IMS, O2 DMS ETSI Profile and O-Cloud Synchronization.
This document contains the initial release of Deployment Use Cases and Potential Requirements.
This specification defines O-RAN O-Cloud hardware accelerator interface functions and protocols for the O-RAN AAL interface, including configuration and management functions, procedures, operations and corresponding solutions. This version brings updated terminology.
This specification focuses on the Common API related to common aspects of accelerator abstraction from an administration and application perspective. This version brings Updates on Terminology, Fault Management, Inventory Functions and HW Installation/Bootstrap.
This document details the AAL specification consisting of the description of the interface, information models and requirements to implement an AALI, for the AAL_DOWNLINK_High-PHY and AAL_UPLINK_High-PHY profiles. This version brings Updates on Naming Conventions
This document describes the white box Outdoor Macrocell Hardware Reference Designs of O-CU, O-DU, and O-RU based on deployment scenario and base station classes specification for O-RAN Split option 7-2x. Specific devices and their part numbers are recorded in respective annex. This version brings revised Section 2.2 the O-DU/O-CU specification and updated Annex.
Initial release of Network Energy Savings technical spec, describing functional procedures for reducing O-RU or O-RU+O-DU energy consumption, and defining related power KPIs.
This document specifies the hardware reference design as required by architecture and requirements for the Outdoor Microcell and deployment scenario and base station classes specifications. This version brings addition of Optional Die to Die Interfacing in section 2.3.2.3.
This specification defines the O-CU and O-DU software architecture, functional blocks, and API definitions. This version includes description of non-GoB massive MIMO flow, configuration and E2 interaction for mMIMO.
This specification defines interoperability test cases for O-CU and O-DU. This version includes new test cases for security, PTP sync and v-OCU and v-ODU.
This document is intended to describe best practices for O-RAN transport based on end-to-end packet switching technology. Version 05.00 document introduces small enhancements to IEEE 802.1X section to align with WG11 efforts.
This document is intended to describe best practices for O-RAN transport Network Element (TNE) management interfaces. Version 06.00 added content in section 9.3 and Annex A in support of the network slicing use case for the transport network.
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.
This document specifies management services for the O-RAN O1 interface and includes requirements, notifications and protocols. This version applies significant re-structuring and clean-up for compliance with O-RAN and ETSI drafting rules.
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. This version applies significant re-structuring and clean-up for compliance with O-RAN and ETSI drafting rules.
The document leverages the existing content in various O-RAN specifications and specifies new use cases for Topology Exposure and Inventory Management. For each use case, the document describes the motivation, resources, processes involved and the data requirements.
This document specifies security requirements and controls for O-RAN defined interfaces and network functions. In version 6 of this technical specifications, multiple changes have been added, including IEEE 802.1X supplicant made mandatory for the vendor to support in O-RU, SBOM requirement made mandatory, O-Cloud infrastructure must now support authentication and authorization of management users, as well as updates on the references and addition to 3GPP references for gNB and eNB. In additional to this, new requirements have been added:
This document contains security protocol specifications for an O-RAN-compliant implementation. In the new version, the image protection section has been updated to cover now all cryptographic operations.
The WG11 threat model and remediation analysis report identifies the various assets that are at risk, outlines the potential security threats that O-RAN system may face, along with security principles on how to mitigate these risks. The report then evaluates the likelihood and potential impact of the identified threats on the O-RAN system.
In this version v6 of the report, new assets and threats against the O-Cloud AAL (Abstraction Acceleration Layer) and the O-RAN applications during their lifecycle phases have been included.
These specifications validate the proper implementation of security requirements and protocols, emulate security attacks, and validate the effectiveness of security mitigation methods. Four new change requests were added in version 4.0. These include image signing and verification (xApps and rApps), security tests of xApps and rApps, security tests of Non-RT RIC, in addition to the previous versions changes.
The O-Cloud security technical report analyses the security of O-Cloud components and interfaces. It includes a risk assessment of the cloud deployment models (Private, Community, Public and Hybrid), identifies the assets that need to be protected, identifies potential security risks and vulnerabilities, and proposes recommendations and best practices for reducing risks and improving the security of O-Cloud. The identified assets, threats and recommendations are intended to be part of O-RAN security related specifications.
In this version v3 of the report, new assets and threats against the O-Cloud AAL (Abstraction Acceleration Layer) have been included.
This technical report on the security for application lifecycle management considers security of O-RAN applications during their lifecycle phases of development, onboarding, and operation. O-RAN applications in the scope of the technical report include VNFs/CNFs as well as software for physical network functions. The report presents key issues developed from identified threats and proposes solutions in order to derive security requirements for technical specifications.
This technical report considers the security log management as far as it applies to entities defined in the O-RAN architecture. The study analyzes a list of key issues on Security logs contents (payload), Security logs transfer mechanisms and Security logs formats/schemas and proposes solutions in order to derive security requirements, intended to be part of O-RAN security related specifications.
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 technical report documents a security analysis for the Shared O-RU with consideration of each of the 5 architectural options. The TR provides assets, threats, risk scoring, and recommended security controls across 6 threat groups. Threat analysis is based upon the STRIDE model and risk scoring is based upon likelihood and impact. Recommended security controls will be used to form normative Shared O-RU security requirements.
This technical report considers the security aspects of the Near-RT RIC platform and xApps, as well as the associated network and management interfaces (E2, A1, O1) and APIs.
The study analyzes a list of key issues in the Near-RT RIC overall architecture and proposes solutions in order to derive security requirements.
This document describes the certification and badging processes and associated detailed technical procedures for the Open Testing and Integration Centres (OTIC) and various other testing entities.
The Objectives and scope of this document:
This version of document brings changes from previous version:
