OpenAirInterface is under GNU GPLv3 license. The full GNU General Public License is included in this distribution in the file called "COPYING".

The OpenAirInterface (OAI) software is composed of six different parts: 

openair1: 3GPP LTE Rel-8 PHY layer + PHY RF simulation

openair2: 3GPP LTE Rel-9 RLC/MAC/PDCP/RRC implementations, eNB application, X2AP. Note that for RLC, the following versions are userL UM_v9.3.0, TM_v9.3.0, and AM_v9.3.0. For PDCP, PDCP_v10.1.0 is used. For RRC, only LITE is used.

openair3: 3GPP LTE Rel9 and 10 MME/NAS, S+P-GW, HSS, S1AP (ENB and MME).

common: some common OAI utilities, other tools can be found at openair2/UTILS

targets: scripts to compile and lauch different system targets (simulation, emulation and real-time platforms, user-space tools for these platforms (tbd)) 

see README files in these subdirectories for more information

see also https://twiki.eurecom.fr/twiki/bin/view/OpenAirInterface/WebHome