33] 1.2.1.1 V-CRAN [27], and [34-38] 1.2.1.2 F-CRAN [39-41] 1.2.2.1 O-RAN [2], and [42-44] 1.2.2.2 NG-RAN [1], and [21, 45, 46] 1.2.2.3 Private 5G [47-54] Options 6 and 8 have been withdrawn of further study by 3GPP due to the various limitations on compatibility between the 5G RAN and the EPC. 1 A Comprehensive Study on 5G and MNOs for private 5G networks. These architectures will be explored in depth in this section and Sect. 1.3. 1.2.1 Cloud-Based 5G Architecture The vast and massive number of devices and applications are foreseen to overwhelm the resources of traditional wireless networks. In 2025, 60 billion devices are expected to be connected to Internet, including 82 UCs, 20 industry-specific UCs, 110 million connected cars, and 1.2 million connected homes [55]. In order to provide a high QoS, e.g., high capacity and coverage, for the end-users, cell densification has been studied as a solution by installing more BSs in RAN [27]. However, cell densification was found to increase the complexity of interference management and intercell coordination. In order to overcome the high density of RAN, cloud-RAN (C-RAN) has been considered for 5G networks and beyond [27]. The C-RAN concept is based on allocating minimal processing of the evolved- universal terrestrial radio access network (E-UTRAN) stack to RRHs while the intensive processing to be performed by BBUs ,27]. Typically, the RRH is a small base station (BS) that is composed of radio units and antennas placed anywhere in the network. It performs minimal processing of E-UTRAN stack, such as L1 or physical (PHY) layer. The rest of the processing of E-UTRAN protocol is migrated to be executed by the BBU. The BBU represents a pool of central and shared computational resources placed in the 5GC or the cloud to perform the intensive signal processing tasks and coordination functionalities [26, 28]. Figure 1.1 presents the C-RAN architecture proposed by IBM corporation [25]. In Fig. 1.1, the RRH communicates with the BBU via a fronthaul link that represents an 