IMT and 5G Network Lifecycle: Architecture, Design, Deployment, and Operations Training Course

Day 1

1. Introduction and Ecosystem Overview

• Multi-dimensional views of the 5G standard: business, standardization, implementation, transport, RAN, Core, and DevOps.

• Clarifying key concepts: 5G, IMT-2020, NG-RAN, NR, 5GC, and 5GS.

• Generational continuity in mobile networks: the seamless progression from 4.5G to 5G across 3GPP Releases 15–17.

2. IMT-2020 Vision

• The User Equipment (UE) as a catalyst for change and a source of new requirements: broadening the UE definition to encompass IoT/mMTC (sensors), RedCap devices (cameras), and UAVs (drones).

• Constraints of 4G/LTE, the limited flexibility of EPC, and associated transport network challenges.

• Emerging requirements for eMBB, URLLC, and mMTC: specific use cases and their impact on RAN and Core design.

• General system requirements that define the 5G network framework.

• Transversal capabilities: Network Slicing, 5QI, CUPS, Multi-access Edge Computing (MEC), and Privacy by Design.

3. Physical Foundations of UE Communication with NG-RAN

• Core radio concepts: Cell, Band, and Channel Width.

• Basics of UE network access: radio protocol stack, MIB/SIB, Cell Selection mechanisms, and the Physical Layer.

• Connection initiation processes: RACH (Msg 1-4), Paging, and RRC.

4. NG-RAN Architecture

• Logical decomposition of the gNB into Centralized Unit (CU) and Distributed Unit (DU).

• Options for Functional Split and their operational implications.

• O-RAN as an alternative/reference framework and standard for enhancing RAN interoperability.

• Separation of Control Plane and User Plane functions.

• The RRC protocol and its role in coordinating UE operations within NG-RAN and NAS tunneling.

5. NG-RAN Mechanisms and Procedures

• PDCP and Radio Bearers.

• Measurement processes: configuration, reporting, and application in other procedures.

• RRC Reconfiguration as a fundamental procedure for all NG-RAN operations.

• Carrier Aggregation and Band Combination strategies.

• The role of the AMF in NG-RAN coordination and the NGAP protocol.

• Handover procedures.

Day 2

1. Transport Network Foundations

• The complexity of transport engineering and dispelling the "just cables" myth: IP/MPLS as a foundational technology.

• Segmentation into Fronthaul, Midhaul, and Backhaul: specific requirements, expectations, and applications (including eCPRI).

• Mapping 5QI parameters from the 5GS domain to IP router QoS settings.

• Distribution and synchronization of time and phase for radio transmission using PTP (IEEE 1588).

2. Inside the SBA Architecture as the 5GC Foundation

• Classic IT stack elements: HTTP/2, JSON, and OAuth2.

• Communication mechanisms for Core Network Functions: Request-Response versus Subscribe-Notify models.

• Key Network Functions (NFs) regarding access handling and traffic termination from NG-RAN: NRF, AMF, SMF, and UPF.

• The NRF as a central coordinator: managing Service Registration and Service Discovery.

• (Conceptual Overview) Stateless architecture and state storage for any NF using UDSF.

• (Conceptual Overview) Load balancing and proxy mechanisms implemented via SCP.

3. Data Path and User Plane Separation

• Data flow from UE to 5GC: correlating NG-RAN interfaces (N2, N3) with specific NFs (AMF, SMF, UPF).

• AMF serving as the entry gateway for the Control Plane (handling termination and demultiplexing of NAS and NGAP signaling).

• UPF as the User Plane core: implementing user data routing and GTP-U tunnel encapsulation.

• PDU Session Establishment call flow: including End-to-End Call Flow and QoS Flow allocation.

• N4 interface (PFCP protocol), TEID allocation, and rules (PDR, FAR) that link radio traffic to external Data Networks (DN).

4. Subscription Management, Identity, and Service Policies

• Database structures: UDR for structured data and UDM for subscriber processing logic.

• The 5G-AKA authentication process involving AUSF, NAS key exchange, and the SUCI mechanism.

• PCF acting as the policy manager and distributor for session, mobility, and SLA policies.

• Binding PDU sessions to PCF instances via BSF — a critical feature for IMS/VoNR.

5. Network Slicing

• Introduction to Network Slicing and configuring the S-NSSAI parameter identifier.

• AMF and SMF instance selection mechanisms based on service profiles via NSSF.

• Introduction to MEC, including the Uplink Classifier (UL CL) and Branching Point within the UPF.

6. External 5GC Exposure and APIs

• SEPP for securing roaming traffic.

• Non-3GPP access: handling subscriber traffic originating outside NG-RAN via N3IWF.

• Exposure and integration with external Application Functions (AF) through the NEF.

7. Analysis of Selected End-to-End Scenarios

• Initial Registration and PDU Session Establishment: involving NRF queries, AUSF credential checks, and fetching subscriptions from UDM and policies from PCF.

• Path Switch Request and UPF relocation procedures for active sessions during Inter-gNB handover.

• Uplink Classifier (UL CL) mechanisms at the UPF and SMF levels for MEC scenarios and Local Breakout (LBO) routing.

• Paging and Network Triggered Service Requests that wake up the UE on UPF initiative in response to downlink traffic.

Day 3

1. Transitional Architecture

• Overview of EPC and E-UTRAN architectures.

• 5G deployment options: Standalone (SA) and Non-Standalone (EN-DC) modes.

2. Coexistence of 5GS and EPS

• EPS Fallback and Redirect mechanisms.

• Hybrid implementations combining PGW-C with SMF and PGW-U with UPF.

• N26 interface enabling Inter-System Handover procedures between MME and AMF.

• Analysis of EN-DC as the predominant variant of MR-DC (Multi-RAT Dual Connectivity).

• DSS (Dynamic Spectrum Sharing) as a spectrum-sharing mechanism.

3. Telemetry, Counters, and Data Correlation

• Monitoring network phenomena via Counters and aggregating them into KPIs.

• Methods for evaluating procedure correctness: Success Ratio, Failure Ratio, and absolute versus percentage values.

• Event correlation: tracking complex procedures that lack dedicated counters.

• Data normalization and gaining a broader perspective on orders of magnitude.

4. Anomaly Diagnostics and Log Analysis

• Identifying issues indicative of software or configuration errors (e.g., "Sleeping Cell").

• Statistical deviations and mapping Cause Values from 3GPP protocols to pinpoint root causes of failures.

5. Chaos Engineering and Troubleshooting

• Basics of managing an open-source 5GC implementation within a dev/cloud environment.

• Testing the Cloud-Native paradigm: replacing core microservice elements without disrupting operations.

• Intentional failure injection to observe failover behavior.

• Simulating NG-RAN degradation and correlating logs on the AMF side.