OpenAirInterface is under OpenAirInterface Software Alliance license.
├── http://www.openairinterface.org/?page_id=101
├── http://www.openairinterface.org/?page_id=698

It is distributed under OAI Public License V1.0. 
The license information is distributed under LICENSE file in the same directory.
Please see NOTICE.txt for third party software that is included in the sources.

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

openairinterface5g
├── ci-scripts: Meta-scripts used by the OSA CI process. Contains also configuration files used day-to-day by CI.
├── cmake_targets: Build utilities to compile (simulation, emulation and real-time platforms), and generated build files
├── common : Some common OAI utilities, other tools can be found at openair2/UTILS
├── doc : Contains an up-to-date feature set list
├── LICENSE
├── maketags : Script to generate emacs tags
├── nfapi : Contains the NFAPI code. A local Readme file provides more details.
├── openair1 : 3GPP LTE Rel-10/12 PHY layer + PHY RF simulation. A local Readme file provides more details.
├── openair2 : 3GPP LTE Rel-10 RLC/MAC/PDCP/RRC/X2AP implementation.
    ├── COMMON
    ├── DOCS
    ├── ENB_APP
    ├── LAYER2/RLC/ with the following subdirectories: UM_v9.3.0, TM_v9.3.0, and AM_v9.3.0. 
    ├── LAYER2/PDCP/PDCP_v10.1.0.
    ├── NETWORK_DRIVER
    ├── PHY_INTERFACE
    ├── RRC/LITE
    ├── UTIL
    ├── X2AP
├── openair3: 3GPP LTE Rel10 for S1AP, NAS GTPV1-U for both ENB and UE.
    ├── COMMON
    ├── DOCS
    ├── GTPV1-U
    ├── NAS
    ├── S1AP
    ├── SCTP
    ├── SECU
    ├── UDP
    ├── UTILS
└── targets: Top-level wrappers for unitary simulation for PHY channels, system-level emulation (eNB-UE with and without S1), and realtime eNB and UE and RRH GW.


RELEASE NOTES:

v1.1.0 -> July 2019. This version adds the following implemented features:
           * Experimental support of LTE-M
             - Single LTE-M UE attachment, legacy-LTE UE attachment is disabled
           * X2 interface and handover (also X2-U interface)
             - In FDD and TDD
           * CU/DU split (F1 interface)
             - Tested only in FDD
           * CDRX
             - Tested only in FDD
           * Experimental eMBMS support (only on UE side)
           * Experimental multi-RRU support
             - Tested only in TDD
          This version has an improved code quality:
           * Simplification of the Build System
             - A single build includes all full-stack simulators, S1/noS1 modes and one HW platform (such as USRP, BladeRF, ...)
           * TUN interface is now used as default for the data plane
             - for UE, eNB-noS1 and UE-noS1
           * Code Cleanup
           * Better Static Code Analysis:
             - Limited number of errors in cppcheck
             - Important Decrease on high Impact errors in CoverityScan
           * Better Test Coverage in Continuous Integration:
             - TM2, CDRX, IF4.5, F1
             - OAI UE is tested in S1 and noS1 modes with USRP board
             - Multi-RRU TDD mode
             - X2 Handover in FDD mode

v1.0.3 -> June 2019: Bug fix for LimeSuite v19.04.0 API
v1.0.2 -> February 2019: Full OAI support for 3.13.1 UHD
v1.0.1 -> February 2019: Bug fix for the UE L1 simulator.
v1.0.0 -> January 2019. This version first implements the architectural split described in doc/oai_lte_enb_func_split_arch.png picture.
            Only FAPI, nFAPI and IF4.5 interfaces are implemented.
            Repository tree structure prepares future integrations of features such as LTE-M, nbIOT or 5G-NR.
            Preliminary X2 support has been implemented.
            S1-flex has been introduced.
            New tools: config library, telnet server, ...
            A lot of bugfixes and a proper automated Continuous Integration process validates contributions.

v0.6.1 -> Mostly bugfixes. This is the last version without NFAPI.
v0.6 -> RRH functionality, UE greatly improved, better TDD support,
        a lot of bugs fixed. WARNING: oaisim in PHY abstraction mode does not
        work, you need to use v0.5.2 for that.
v0.5.2 -> Last version with old code for oaisim (abstraction mode works)
v0.5.1 -> Merge of bugfix-137-uplink-fixes. It includes stablity fixes for eNB
v0.5 -> Merge of enhancement-10-harmony-lts. It includes fixes for Ubuntu 16.04 support
v0.4 -> Merge of feature-131-new-license. It closes issue#131 and changes the license to OAI Public License V1.0
v0.3 -> Last stable commit on develop branch before the merge of feature-131-new-license. This is the last commit with GPL License
v0.2 -> Merge of enhancement-10-harmony to include NGFI RRH + New Interface for RF/BBU
v0.1 -> Last stable commit on develop branch before enhancement-10-harmony