ating costs over legacy RAN deployments by a sizeable extent, allowing the operators to focus on innovation and value delivery to their customers. 5G Infrastructure Design System Integration Cost? Managed by Managed Services Provider Services Services Support Services Support Software Support Software Hardware System Hardware Open RAN Open RAN Pre-Open RAN Network in the Network in the Networks Introduction Long Term Figure 12.14 - Management paradigms of RAN infrastructure [image credit: Sanya] Next, we look at the full view of the O-RAN architecture in Figure 12.15 (see https ://www.o- ran. org). The O-RAN architecture comprises the following elements: Service Management & Orchestrator (SMO): SMO governs the orchestration, management, and automation of RAN elements and supports O1, A1, and O2 interfaces. Non-real-time RAN Intelligent Controller (Non-RT RIC): Non-RT RIC allows non-real-time control and optimization of RAN elements and resources. It facilitates Artificial Intelligence (AI) and Machine Learning (ML) capabilities for training and updating the models. Near-real-time RAN Intelligent Controller (Near-RT RIC): Near-RT RIC enables near-real-time control and optimization of O-RAN elements and supports the E2 interface for the collection of fine-grained data and actions. It helps to optimize and enrich the control function of the RAN. O-RAN Central Unit (O-CU): O-CU consists of O-RAN Central Unit - Control Plane (O-CU-CP) and O-RAN Central Unit - User Plane (O-CU-UP). O-CU also hosts the Radio Resource Control (RRC), Service Data Adaptation Protocol (SDAP), and Packet Data Convergence Protocol (PDCP) protocols. O-RAN Distributed Unit (O-DU): O-DU hosts Radio Link Control (RLC)/Medium Access Control (MAC)/high-PHY layers, where PHY is the physical and electrical characteristics of the network. O-RAN Radio Unit (O-RU): O-RU hosts the low-PHY layer and Radio Frequency (RF) processing layers. Understanding O-RAN Together these components provide the full range of network functionality of O-RAN: Design Invento