Duranta OpenAirInterface RAN delivers and maintains an open-source cellular wireless software stack for 4G, 5G and future networking technologies. It supports simulation, prototyping, and end-to-end deployments on Commercial-Off-The-Shelf (COTS) hardware. Built for research and experimentation, it provides standard-compliant interfaces and is released under the Collaborative Standards Software License v1.0 (CSSL).

• CSSL v1.0
• Licenses

The source code is distributed under CSSL v1.0. Some files, such as for orchestration, are distributed under MIT license. Documentation is distributed under Creative Commons Attribution 4.0 International license.

All the files without an explicit copyright header have an implicit "Copyright of OpenAirInterface Authors".

Please see NOTICE for other licenses which are used in the software.

In the past OAI source code has been re-licensed sometimes, here is the history:

1. CSSL v1.0 starting tag 2026.w14
2. OAI Public License v1.1 starting tag v1.0 till af4b0d53
3. OAI Public License v1.0: starting tag v.04 till v1.0
4. GPL 3: starting tag v.0 till v.04 (only initial implementation of 4G)

• General overview of documentation
• The implemented features
• System Requirements for Using OAI Stack
• How to build
• How to run the modems

Not all information is available in a central place, and information for specific sub-systems might be available in the corresponding sub-directories. To find all READMEs, this command might be handy:

find . -iname "readme*"

The OpenAirInterface (OAI) software is composed of the following parts:

openairinterface5g
├── .github           : GitHub workflows and repository configuration
├── LICENSES          : Preferred, deprecated, and exception license texts
├── charts            : Helm charts for running 4G and 5G physical simulators
├── ci-scripts        : OAI CI framework, test scenarios, and configuration files
├── CMakeLists.txt    : Top-level CMake configuration
├── cmake_targets     : Build and dependency-management utilities
├── common            : Common configuration, utilities, and shared infrastructure
├── doc               : Documentation
├── docker            : Dockerfiles for building Ubuntu, RHEL, and Rocky Linux images
├── executables       : Top-level gNB, eNB, UE, CU, DU, and O-RU entry points
├── fronthaul         : Native OAI 7.2x fronthaul implementation
├── maketags          : Script to generate Emacs tags
├── nfapi             : FAPI and nFAPI implementations for the MAC-PHY interface
├── openair1          : LTE and NR physical layer
├── openair2          : MAC, RLC, PDCP, SDAP, RRC, and application protocols
├── openair3          : NAS, S1AP, NGAP, GTP, and related layer-3 protocols
├── openshift         : OpenShift deployment resources
├── radio             : Radio and simulation drivers
├── targets           : Legacy configuration files and deployment resources
├── tests             : Component and integration tests
└── tools             : Developer and CI analysis, formatting, and plotting tools

You can ask your question on the mailing lists.

Your email should contain below information:

• A clear subject in your email.
• For all the queries there should be [Query] in the subject of the email and for problems there should be [Problem].
• In case of a problem, add a small description.
• Do not share any photos unless you want to share a diagram.
• OAI gNB/DU/CU/CU-CP/CU-UP configuration file in .conf format only.
• Logs of OAI gNB/DU/CU/CU-CP/CU-UP in .log or .txt format only.
• In case your question is related to performance, include a small description of the machine (Operating System, Kernel version, CPU, RAM and networking card) and diagram of your testing environment.
• Known/open issues are present on Github, so keep checking.

Always remember a structured email will help us understand your issues quickly.