Leading the industry towards open, interoperable interfaces and RAN virtualization.

O-RAN Alliance Overview

O-RAN Alliance members and contributors have committed to evolving radio access networks around the world. Future RANs will be built on a foundation of virtualized network elements, white-box hardware and standardized interfaces that fully embrace O-RAN’s core principles of intelligence and openness. An ecosystem of innovative new products is already emerging that will form the underpinnings of the multi-vendor, interoperable, autonomous, RAN, envisioned by many in the past, but only now enabled by the global industry-wide vision, commitment and leadership of O-RAN Alliance members and contributors.

The O-RAN Alliance was founded by operators to clearly define requirements and help build a supply chain eco-system to realize its objectives. To accomplish these objectives, the O-RAN Alliance’s work will embody two core principles: 




It would be impossible to bring service agility and cloud scale economics to the RAN without openness. Open interfaces are essential to enable smaller vendors and operators to introduce their own services, or customize the network to suit their own unique needs. Open interfaces also enable multi-vendor deployments, enabling a more competitive and vibrant supplier ecosystem. Similarly, open source software and hardware reference designs enable faster, more democratic and permission-less innovation.



Networks will become increasingly complex with the advent of 5G, densification and richer and more demanding applications. To tame this complexity, we cannot use traditional human intensive means of deploying, optimizing and operating a network. Instead, networks must be self-driving, they should be able to leverage new learning based technologies to automate operational network functions and reduce OPEX. The O-RAN alliance will strive to leverage emerging deep learning techniques to embed intelligence in every layer of the RAN architecture. Embedded intelligence, applied at both component and network levels, enables dynamic local radio resource allocation and optimizes network-wide efficiency. In combination with standardized southbound interfaces, AI-optimized closed-loop automation is achievable and will enable a new era for network operations.



Gabriel Brown, Principal Analyst at Heavy Reading, talks with Leading O-RAN Alliance Operators. Source: Light Reading


O-RAN Architecture

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The O-RAN Reference Architecture is designed to enable next generation RAN infrastructures. Empowered by principles of intelligence and openness, the O-RAN architecture is the foundation for building the virtualized RAN on open hardware, with embedded AI-powered radio control, that has been envisioned by operators around the globe. The architecture is based on well-defined, standardized interfaces to enable an open, interoperable supply chain ecosystem in full support of and complimentary to standards promoted by 3GPP and other industry standards organizations.

O-RAN Alliance Organizational Structure

Founded in February 2018 by AT&T, China Mobile, Deutsche Telekom, NTT DOCOMO and Orange, the O-RAN Alliance was established as a German entity in August 2018. The management structure consists of an Operating Board made up of 15 operators and a Technical Steering Committee (TSC) co-chaired by Dr. Sachin Katti, Professor at Stanford University and Dr. Chih-Lin I, Chief Scientist of Wireless Technologies at China Mobile. The remaining TSC members are made up of the chairs and co-chairs of each technical workgroup. Workgroups are made up of both operators and contributors.


The O-RAN specification work has been divided into technical workgroups, all of them under the supervision of the Technical Steering Committee. The technical workgroups have specific focus areas and are open to all members and contributors.

  • WG1: Use Cases and Overall Architecture Workgroup. It has overall responsibility for the O-RAN Architecture and Use Cases. Work Group 1 identifies tasks to be completed within the scope of the Architecture and Use Cases and assigns task group leads to drive these tasks to completion while working across other O-RAN work groups

  • WG2: The Non-real-time RAN Intelligent Controller and A1 Interface Workgroup. The primary goal of Non-RT RIC is to support non-real-time intelligent radio resource management, higher layer procedure optimization, policy optimization in RAN, and providing AI/ML models to near-RT RIC.

  • WG3: The Near-real-time RIC and E2 Interface Workgroup. The focus of this workgroup is to define an architecture based on Near-Real-Time Radio Intelligent Controller (RIC), which enables near-real-time control and optimization of RAN elements and resources via fine-grained data collection and actions over E2 interface.

  • WG4: The Open Fronthaul Interfaces Workgroup. The objective of this work is to deliver truly open fronthaul interfaces, in which multi-vendor DU-RRU interoperability can be realized.

  • WG5: The Open F1/W1/E1/X2/Xn Interface Workgroup. The objective of this work is to provide fully operable multi-vendor profile specifications (which shall be compliant with 3GPP specification) for F1/W1/E1/X2/Xn interfaces and in some cases will propose 3GPP specification enhancements.

  • WG6: The Cloudification and Orchestration Workgroup. The cloudification and orchestration workgroup seeks to drive the decoupling of RAN software from the underlying hardware platforms and to produce technology and reference designs that would allow commodity hardware platforms to be leveraged for all parts of a RAN deployment including the CU and the DU.

  • WG7: The White-box Hardware Workgroup. The promotion of white box hardware is a potential way to reduce the cost of 5G deployment that will benefit both the operators and vendors. The objective of this working group is to specify and release a complete reference design to foster a decoupled software and hardware platform.

  • WG8: Stack Reference Design Workgroup. The aim of this workgroup is to develop the software architecture, design, and release plan for the O-RAN Central Unit (O-CU) and O-RAN Distributed Unit (O-DU) based on O-RAN and 3GPP specifications for the NR protocol stack.