f ONAP. So far, open source telecom projects have been primarily targeting the CN. While it technically harder to apply the same concept to RAN, because RAN cannot be fully imple- mented in software, there are attempts to do SO in the following organizations/projects: O-RAN Alliance OSA: OpenAirInterface Software Alliance. While OSA is primarily focused on open source LTE and 5G implementations, both TIP and O-RAN have much bigger scope, with open source being a part of it. TIP OpenCellular (OC) is an ecosystem of open source projects focusing on hardware, software, testing automation, and manufacturing and building tools for ease of deployment and operation of a cellular network. O-RAN Working Group 7 (WG7) has been established to promote 5G white box hardware, while O-RAN WG8 is developing software that conforms to O-RAN specifications. 2.11 Competition It is important to point out that regardless of the maturity of the open source projects mentioned above (some of which are in rather initial stages of development at the time of writing this book), it is unlikely that an operator would be able to simply download and deploy such software. As has been the case in other industries using open source, oftentimes a third-party integrator is involved, whose role is to "assemble" and, more importantly, test and certify the final product based on open source components. While open source CNs and OAM are beyond the scope of this book, for more details about open source RAN, refer to Section 6.3. Note: when dealing with open source, an important consideration is a license that an open source project is using. There are many open source licenses, which vary in particular in terms of the amount of freedom allowed and also in terms of restrictions imposed. A full overview of this subject is beyond the scope of this book; here we provide a few examples of the most popular open source licenses: A BSD license is considered "permissive", imposing very few restrictions on the use and distribution of the software, including re-use