5G Core - Architectures, Concepts and Call Flows

Understand why 5G is needed beyond 4G, driven by enhanced mobile broadband, ultra reliable low latency, and massive machine type communications, and how it targets IMT 2020 versus IMT advanced.

Explore the three 5g use cases—enhanced mobile broadband, ultra reliable low latency, and massive machine type communications—and their distinct requirements, including latency, mobility, energy efficiency, and network slicing.

Meet 5G requirements using spectral efficiency tools like massive MIMO and millimeter-wave spectrum. Adopt spectrum sharing and advanced network architectures such as software defined networking, virtualization, and mobile edge computing.

Outlines the 3GPP 5G timeline across standards, deployments, and research, detailing release 15/16, FR one/FR two terminology, and private networks, industrial IoT, and ultra reliable low latency.

Explore standalone and non-standalone 5G architectures and migration options, connecting 5G NR, LTE, and 5G core. See how edge data centers, cloud-native cores, and network slicing enable low-latency, high-speed services.

Explore the enabling technologies behind the 5G core, including virtualization, cloud native, containers, and microservices, and how automation and orchestration drive self-healing and real-time scaling.

This lecture explains virtualization in 5G, showing how virtual machines run on commercial off-the-shelf hardware via a hypervisor, decoupling software from proprietary hardware to enable scalable, cost-efficient, automated networks.

Explore cloud native architectures in telecom, including infrastructure agnostic apps, microservices, lifecycle management, and resiliency, with orchestration via Kubernetes and OpenStack.

Explore how containers in the 5G core architectures compare to virtual machines, emphasizing container orchestrators like Kubernetes, containerized microservices, and faster scalable workloads.

Discover microservices as the backbone of 5G core architecture, where network functions split into independent services communicating via well-defined APIs, enabling scalable, upgradeable, and easier-to-debug systems.

Explore automation and orchestration in 5G, enabling lifecycle management of microservices-based applications and infrastructure, boosting rollout speed, upgrade ease, and reliability through core-network automation and AI/ML integration.

Learn 5g core architecture through the service based view and the point-to-point interface view, where network functions communicate via APIs and interfaces such as N1, N2, N3, N4, and N6.

Explore the 5g core service-based architecture, where network functions act as service producers and consumers, using http restful APIs on a common channel, with both SBA and point-to-point views.

Explore the 5g core point-to-point interfaces, mapping network functions to N17 links, and compare with service-based architecture, highlighting producers, consumers, and the interaction between functions.

Describe the AMF in the 5G core, its N1, N2, and N11 interfaces, and its role with SMF, PCF, LMF, and unified data management for authentication and registration.

Explore how the AMF manages connection management states idle and connected, paging, and service request procedures, with N1, N2, N3 interfaces and 5G GT identifiers.

Sits between connected and idle, the AMF RRC inactive state in 5G enables quick resume to connected by preserving the inactive access stratum context and monitoring the paging channel.

Explore how the session management function (SMF) sets up connectivity towards data networks and manages the user plane, including session establishment, modification, and release.

Examine how the user plane function (UPF) processes and forwards user data, anchors traffic to external networks, and handles charging data records, usage records, and buffering for idle mode subscribers.

Explore 5g service session continuity modes: mode one, mode two, and mode three, focusing on PDU session continuity, PSR selection, and UPF handovers with IP address and latency implications.

Connect UPFs in series via the N9 interface to preserve IP continuity during network wide mobility and enable selective data flow with uplink classifiers for MEC and roaming.

Explain how 5G uses flows as the finest QoS granularity, multiplexing QoS flows with flow IDs within a single radio bearer in a PDU session.

Introduce reflective QoS in 5G to minimize signaling by marking downlink packets for uplink processing and reusing the same flow IDs across downlink and uplink.

The NRF stores profiles of network functions, including addresses, capacity, and services, enabling service consumers to discover and select providers without static mappings, via http put and http get.

The unified data repository (UDR) stores subscription and policy data and serves UDM, PCF, and NEF, with ESF for authentication and IAR for device identity.

Policy control function (PCF) governs session management and mobility policies, coordinating with AMF, SMF, UPF, and charging function, and pushes non-3gpp access and network slice selection policies.

Explore how 5g network slicing creates logical networks on shared hardware to support enhanced mobile broadband, ultra reliable low latency, and massive Iot, guided by the network slice selection function.

Explore the subscription permanent identity (SUPI) in 5G core, including how MCC-MNC-based identifiers, UDR provisioning, and network-specific identifiers support roaming and privacy with the subscription concealed identifier.

Derive the subscription concealed identity as a privacy-preserving, one-time use identifier derived from the permanent identity via the home network public key, enabling the network to recover the permanent identity.

Explore the permanent equipment identifier (pi) in 5G, representing IMEI or IMEI with software version, like 4G. See how the equipment identity registry uses pi to blacklist devices.

Explain how 5G GUTI maps to 4G GUTI to enable seamless registration and data continuity as devices switch between networks, using AMF and MME context transfer and co-located deployments.

Explore 5G security architecture and network access security, focusing on integrity and ciphering. Learn NAS-based authentication across 3GPP and non-3GPP, and security entities like SIF, RMF, RPF, and DIF.

Demonstrates 5G network access security, detailing RPF, authentication server function, security anchor function, and sid concealment in UDM/UDR, compares to 4G, and covers NAS authentication and AKA Prime.

Explore the 5G core key hierarchy from the master key to cipher and integrity keys and how they secure authentication across home and serving networks.

Explore how 4G and 5G core networks interwork to deliver seamless mobility across networks. Examine interfaces like N26 and S5, and the SMF/UPF/MME/AMF roles that anchor sessions.