andard options will be deployed in the field. Fur- thermore, there are still many Standards Developing Organizations (SDOs) and industry fora working on technologies that may be considered competition (e.g. LoRa and the Institute of Electrical and Electronics Engineers [IEEE]), or may complement 3GPP stan- dards (e.g. Broadband Forum [BBF], Open Radio Access Network [O-RAN], Small Cell Forum, etc.). Open source, which was extremely successful in the enterprise and data centers, is increasingly finding its way into telecom networks. There are number of open source LTE Evolved Packet Core (EPC) implementations available (e.g. Magma), open source Operations, Administration, and Maintenance (OAM) frameworks (e.g. Open Network- ing Automation Platform [ONAP] and Open Source Mano [OSM]), and finally even RAN implementations (e.g. OpenAirInterface). Open source may be considered an alternative to standardization, and while it is hard to see how it can replace standards for the radio interface, at least in the CN and even in RAN it may become a viable alternative. RAN sharing is likely to become more important in driving down costs; it may eventually evolve into a neutral host RAN sharing model. 2.3 Spectrum 5G will not only trigger a new round of competition among the usual cellular players, for example, operators, network and handset vendors, but also a competition between tech- nologies and whole market segments. 5G is often touted as the next wireless revolution and the promises made are indeed somewhat grandiose. There is no doubt that the tech- nology is capable of delivering these promises, provided there is a viable business model to support them. In this book, we illustrate how 5G market drivers affect RAN architecture and deployment considerations from the perspectives of increased throughputs, reduced latency, network densification, and competition within the traditional wireless ecosystem and between incumbents and new players. 2.3 Spectrum 2.3.1 Spectrum Needs As with many previous generations of cellular te