n 3GPP specification [94], the requirements of several industrial applications have been identified such as the reliability, latency, positioning accuracy, and battery lifetime. Deploying a private 5G network in the enterprise's defined premises is fun- damental to meet the demands of the various industrial applications. In addition, it offers a full control on the 5G RAN and core, and thereby several benefits can be gained in terms of coverage, deployment flexibility, availability, privacy, and security. Furthermore, the cost of accessing the licensed spectrum might be eliminated, thanks to the NR-unlicensed (NR-U) and the new unlicensed bands. The main benefits of the private 5G networks can be summarized as follows: A Comprehensive Study on 5G Table 1.4 Research works to tackle challenges for 5G architectures Reference Challenge Methodology and outcomes [77-80] Resource In [77], a game theory algorithm has been proposed to allocation maximize the utilization of the computational resources in C-RAN by distributing the resources of BBU pool efficiently. The simulation results showed that this algorithm improves the bottleneck management and the fulfillment level by 13%. In [78], a resource allocation algorithm for H-CRAN was proposed by using cooperative game approach and the constructive greedy approach. The proposed algorithm was found to outperform earlier research works in the literature in terms of average data rates, access rates, and throughput. In [79], joint resource allocation and admission control scheme was proposed to maximize the number of UEs in a network slice subject to a desired level of QoS. By comparing this algorithm to the existing baseline, the maximum number of UEs in a slice was increased effectively. In [80], a reinforcement learning algorithm has been developed to optimize the radio resource management (RRM) in O-RAN [81-84] Energy In [81], an energy allocation and cooperation algorithm was efficiency proposed to improve the long-term energy efficiency in C-RAN. The problem has been fo