6G, 5G, 4G, 3G, 2G Telecom Technologies - Foundation

Trace the evolution of telecom core networks from 2G to 5G, covering GSM, GPRS, UMTS, 4G LTE, and the shift to split and flat architectures, with IMS voice.

Trace the evolution from 2G GSM to GPRS data services and map how radio access and core networks, with MSC, HLR, VLR, SGSN, and GGSN, handle voice and data.

Understand the 3G UMTS network with split control and user planes. Trace voice and data flows from node B and RNC through MGW, HLR/VLR, SGSN, GGSN to PSTN or internet.

Explore the IMS architecture that enables voice, video, and messaging over IP, replacing the legacy TDM PSTN backbone and supporting VoIP services through CSCF components and HSS and application servers.

Trace the evolution from 3G towards 4G, noting IMS, HSPA, SAE, MME, and gateway concepts that define LTE architecture and future AMF in 5G.

Explore the 4G LTE standalone core network, detailing how MME, HSS, SGW, PGW, and PCRF coordinate authentication, sessions, and QoS for data and voice services.

Compare LTE, LTE advanced, and LTE advanced pro across architecture and radio access enhancements, including virtualization and cloudification in releases 13 and 14, to enable 4.5g and nb-iot.

Explore the core network of 4G and 5G, including standalone versus non-standalone deployments, secure connectivity, mobility and session management, QoS, and the desegregated CUPS architecture enabling network slicing.

Explore the 5G core architecture, including disaggregated control and user planes, CUPS architecture and key nodes like AMF, AUSF, UDM, PCF, SMF, and UPF, plus PDU sessions and QoS.

Explore 5g service-based architecture: modular core, common interface, software defined networking and virtualization; network functions communicate via Rest APIs for service registration, discovery, and policy-driven requests.

Learn ITU-defined 4G key capabilities (releases 8–14), including 1 Gbps downlink, 10 ms latency, and mobility up to 350 kilometer per hour, plus 0.1 million IoT devices per square kilometer.

Explore how 5G enables enhanced broadband, ultra-reliable low latency, and massive machine-to-machine connectivity (eMBB, m2m, URLLC), delivering 4K video, fixed wireless access, smart cities, V2X, and real-time augmented reality.

Explore ITU's IMT 2020 5G key capabilities, including 20 Gbps cell-level peak rate, 100 Mbps downlink, 1 ms latency, and three times more efficiency in spectrum.

Discover 6g key capabilities defined by the ITU, including 50x 4g peak rates, 1000 gbps throughput, mobility to 1000 km/h, 0.1 ms latency, 10M connections, and 300x energy efficiency.

Navigate to the resources folder in the last lecture of your Udemy course to download PDFs and slides for future reference, interviews, or projects.

Explore spectrum management in 4g and 5g, covering spectrum bands, bandwidth, uplink and downlink duplex schemes, frame structure, modulation, coding, mimo, and carrier aggregation for ultra reliable low latency services.

Assess 4g lte spectrum allocation from 700 mhz to 3.5 ghz, including fdd and tdd duplexing for uplink and downlink, and the spectrum-capacity trade-off.

Explore how 5G spectrum, FR1 and FR2 bands, and millimeter-wave bandwidth trade coverage for throughput, guiding telcos to mix low and high frequencies for optimal 5G deployment.

Explore 4g duplex schemes: fdd and tdd, plus half duplex fdd. Fdd uses separate uplink and downlink bands; tdd shares one band in time.

Explore how LTE allocates resources on the physical layer using a 10 ms radio frame with 10 subframes, 0.5 ms slots, seven OFDM symbols, and resource blocks.

Explore 4g frame structures: fdd uses separate uplink and downlink bands, while tdd shares a frame with a guard period and special subframes. Learn about cyclic prefixes and periodicity effects on uplink-downlink allocation.

5g radio uses a ten millisecond frame divided into ten subframes, with 14 ofdm symbols per slot and 15 khz subcarriers in a ten megahertz spectrum for flexible time–frequency resources.

Explore 5G resource grids, examining resource blocks of 12 subcarriers, 15kHz to 240kHz numerologies, and how subcarrier spacing and OFDM symbol duration affect resource elements, bandwidth parts, and latency.

Modulation uses amplitude, phase, or frequency changes to create carrier signals, enabling smaller antennas, less interference, and higher throughput through schemes like qpsk and 16 qam in ofdm.

Explore OFDMA in LTE, an orthogonal frequency division multiplexing technique that saves spectrum by overlapping subcarriers and enabling combined time and frequency resource allocation for efficient LTE frame design.

Explain how timing advance in 4g lte aligns uplink transmissions to the base station, preventing interference from distance, and note guard periods and cyclic prefix reduce errors in tdd.

Explore uplink power control in 4g lte, comparing open loop and closed loop mechanisms. Learn how path loss and sinr guide transmit power to reduce interference and maintain quality.

Explore LTE carrier aggregation by combining multiple frequency bands and carriers to boost data rates, including inter band and intra band schemes, with the Mac layer driving end-user throughput.

Explore antenna arrays and how mimo and beamforming shape radiation patterns. Compare single versus multi-element arrays, noting how increasing elements raises gain and forms beams across theta and azimuth angles.

Explore MIMO, the multiple input multiple output technique, transmitting multiple streams to improve diversity gain and data rates through spatial diversity and spatial multiplexing, with antenna configurations and deployment considerations.

Explore spatial multiplexing in MIMO, detailing static beamforming for a single user and dynamic beamforming for multiple users, highlighting when to use multi-user MIMO for higher data rates.

Massive MIMO, combined with beamforming, enables 8x8 arrays in lower and mid bands and improves indoor coverage at higher frequencies, leveraging active antenna systems for stronger signals.

Examine the 4g LTE physical layer, detailing time-frequency resource allocation, reference signals, initial access channels (pss, sss, pch), and downlink channels (pdcch, pdsch) plus mimo and CSI reference signals.

Understand the 5g nr physical layer dimensioning, including time and frequency resource allocation, 15 khz subcarrier spacing, and synchronization signals and broadcast channels, PDCCH, and reference signals.

Access the resources folder to download PDFs and slides for each section, enabling quick refresher, interview prep, or project reference. Locate end-of-section documents in the last lecture for ongoing learning.

Trace the evolution of radio access networks from hardware driven systems to cloudification and virtualization, plus open architectures that enable disaggregation for lower latency and a multi-vendor ecosystem.

Identify the four-stage evolution of the RAN, from stage one’s proprietary hardware to stage four’s cloud native, containerized, self-healing, auto-scaling network.

Openran's split architecture desegregates the radio access network, moving real-time scheduling to the radio unit, while registration, initial qos, and ciphering move to a centralized unit.

Explore how the disaggregated radio access network splits layer tasks between the du and cu, while higher layers cover modulation, coding, scheduling, and rrc with pdcp security and sgap qos.

Explore Oran's split-architecture options from 1 to 8 under 3GPP, and why option 7.2 is proposed as the optimum due to radio unit weight and stringent RU-DU connectivity.

Explore virtualization and orchestration in telecom networks, including network function virtualization, NFV managers, and VNF orchestration, enabling virtual ODU/OCU resources and scalable 5G Openran services.

Turn hardware into virtual machines in openran via a hypervisor; the orchestrator provisions 5g services and core nodes, with the virtualized infrastructure manager and vnf manager enabling them.

OpenRAN cloud enables on-demand access to a shared resource pool across central and distributed units, enabling dynamic scaling via edge or regional clouds.

Cloud RAN uses intelligent controllers—near real time and non real time—to optimize network parameters with third‑party ML tools, enabling quality of service improvement and beamforming through orchestration via ONAP.

Operators favor virtualized RAN first, evolving from distributed RAN toward cloud RAN. Centralized RAN introduces cloud resources allocated across sites, with mid-haul costs and potential wireless mid-haul.

Explore open radio access network concepts and shift from proprietary to non-proprietary ecosystems. Examine disaggregation of hardware and software, cloud use, and machine learning potential in open radio access network.

Explore open ran standards, the telecom infra project, operator alliances, small cell forum open front-haul interface, open ran policy coalition, plus software-focused innovation by open alliance and Linux Foundation.

Define OpenRan design goals that reduce capex and opex in the radio access network while enabling interoperability, vendor independence, and open source, with AI-driven automation.

Explore open radio access networks and their design challenges, including legacy integration, brownfield deployments, multi-vendor interoperability, and ensuring robust fronthaul and midhaul connectivity with tight latency.

Access the resources folder in the last lecture to download the pdfs and slides for this section. Keep these documents handy for refreshers, interviews, or a project.

Examine the transport network that connects the radio access network to the core, covering disaggregated RAN, latency management, wireless backhaul, and service level architecture for 5G ecosystems.

Outline the three subnetworks—radio access network, core network, and transport network—exploring microwave and fiber backhaul, desegregation into central and distributed units, and the role of midhaul and front hall in 5G.

Explore wireless microwave and fiber backhaul in transport networks, focusing on chain and star topologies; learn how hub sites aggregate last-mile traffic and connect to the exchange via fiber switches.

Explains how microwave backhaul uses large and small antennas to bridge masts over 14 km, linking a hub site to another island and enabling transport network connectivity.

Trace the evolution from traditional backhaul to open ran with du and cu, mid-haul and fronthaul links, rising capacity and the evolved sipri protocol for ultra-low latency.

Openran desegregation drives a new eCPRI protocol to replace legacy CPRI, enabling higher fronthaul throughput from front hall to baseband unit, up to 100 gbps.

Explore wireless mid hall transport connectivity in Openran. Use E band 70–90 GHz to balance distance, capacity, and cost versus fiber, while noting challenges and trade-offs.

Explore how the E band mid-haul delivers high capacity, up to ten gigabits per second, with low license costs while balancing antenna size, hop length, and availability.

Analyze how 5G transport evolves to deliver ITU’s ultra-reliable low-latency, enhanced mobile broadband, and m2m services by disaggregating du/ru, deploying edge or regional clouds, and ensuring ultra-fast fronthaul.

Navigate to the resources folder in your Udemy course to download the section documents, then use the PDFs for future refresher, interviews, or projects.

Explore the 4G core network architecture with MME, HSS, S-GW, and PGW for authentication and mobility, then examine the 5G core functions like AMF, SMF, UPF, PCF, UDM, and slicing.

Explore how a standalone 4G core network authenticates users with MMI and home subscription subsystem, establishes sessions through SG and PG, and enforces QoS via PCF for data and voice.

Understand how the mobility management entity in the 4g core handles signaling, security, session establishment, handovers, and cross technology coexistence with 2g/3g for seamless connectivity.

Explore the serving gateway’s role in the 4g core, including packet marking, mobility anchoring for inter-eNodeB handovers, routing and buffering, lawful interception, QoS with DSCP and retention priority, and accounting.

The packet data network gateway (PGW) serves as entry and exit point in the 4G core, allocates IP addresses, enforces QoS and data quotas with PCF, and supports lawful interception.

The home subscriber server stores subscription data in the core network, enabling identification, authentication, roaming eligibility, and provisioning of access profiles for 4g and 3g services like voice, data, sms.

Understand the policy charging and rule function (pcf) and its role with the pkg in defining per-user data limits, billing, rating, and subscriber data for tailored quality of service.

Explore 5g core architecture with disaggregated control and user planes, detailing amf, udm, ussf, pcf, smf, and upf for access, policy, pdu sessions, contrast reference point with service-based architectures.

Explore the 5g core service-based architecture, a modular framework where network functions communicate through a common interface using rest api, sdn, and nfv.

amf in 5g core manages policy with pcf, authenticates users with usf and udm, relays signaling between smf and ue, and secures mobility and signaling encryption via n1 and n2.

Explore the AMF hierarchy and deployment regions, where AMF regions define groups and pointers map users and cell sites to a globally unique temporary ID for regional authentication.

Master the 5G core session management function (SMF) that orchestrates PDU sessions, retrieves policies to configure the UPF, and supports roaming and charging via the AMF.

Explore the 5g core node upf, detailing end-to-end user plane routing, buffering and qos management, ingress and egress data rates, policy enforcement, and mobility management across the core network.

Explore the 5G policy control function (PCF) and how it manages mobility policy control, service restrictions, radio frequency selection priority, slice selection, Non-3GPP network discovery, and session management.

Explore how unified data management generates authentication credentials, protects permanent identity privacy, and coordinates with UDR, RMF, and SMF to securely support UE access and PDU session management.

Explore the 5G core network data analytics function NWDAF, which collects data from the PCF and NSSF to fuel machine learning insights that optimize resource allocation and network slicing.

The NSSF enables core network slicing by selecting network slice instances and the AMF for each user, guided by NSI information from the NSF, including service type and slice differentiator.

The network repository function (NRF) in the core network stores all network function data, manages service access and authorization, automates configuration, and helps discover suitable service candidates for each function.

Navigate to the resources folder in your Udemy account, download the section document, and use the slides for future refresher, interview prep, and project reference.

Explore how 2G to 6G telecoms connect users and core networks through registration, call flows, and identity management, including IMSI, GUTI, cell IDs, and interworking across 4G and 5G.

Explains registration procedures for scenarios: first-time power-on, movement between location area codes, periodic registration, and emergency registration, and the flow from user to base station to core network enabling paging.

Explore the 4g call flow from user equipment to the core network, detailing registration, attach requests, authentication, session setup, and policy-based QoS managed by HSS and PCF.

Understand the 5G call flow from user equipment to the radio access and core networks during initial access, covering synchronization, system information blocks, cell selection, PLMN identity, and RRC setup.

The lecture explains end-to-end 5g call flow from registration to core, detailing nas signaling, rmf authentication with ausf and udm, and pdu session setup by smf with upf handling data.

Explore how 4g network identity components identify cells, including EU trans cell global identity, enodeb IDs, MCC/MNC, node ID, and PCI, and explain PCI reuse by geography.

Define the 5g identities: CGI from the PLMN id and cell id, and PCI using primary and secondary synchronization signals (0–2, 335) for area-specific unique IDs.

Learn how IMSI uniquely identifies subscribers for core network authentication, stored in SIM or HSS, and how MCC, MNC, and MSIN form an IMSI with a tmsi after initial access.

Assign a global unique temporary ID (GUTI) after LTE attach to protect the user's permanent IMSI, with GUTI tied to the ME code and TMC for secure paging.

Gooty is a globally unique temporary identifier allocated by the AMF to the Eui for 3GPP and non-3GPP access, combining the PLM identity and AMF identifier with MCC and MNC.

Discover three key 5g identities: supi, a globally unique subscriber identifier provisioned in udm/udr with 15 digits; suci, a protected private identity, and the network access identity, formatted as user@realm.

Explore multi-technology access across 4G, 3G, and 2G with a single USIM authentication and common subscription data, guided by signal-strength based priority and mobility management.

Maintain seamless session continuity across 2G-4G by leveraging SGSN, GGSN, and PGW, while upgrading GPRS to PGW functionality or replacing SGSN with PGW based on deployment.

Navigate to the resources folder in the last lecture to download PDF files and slides for each section, then refer to them for refresher, interviews, or project work.

Explore six g advances and how virtualization, nfv, sdn, and cloud enable end-to-end telecom networks, including radio access, core, and transport architectures.

Examine how 6G delivers immersive, faster connectivity—about 50x 5G—with AI, hyper-reliable low latency, and ubiquitous device connectivity. It highlights IMT 2030, cloud, virtualization, and security for sustainable, intelligent networks.

Explore virtualization of hardware resources to create virtual compute, storage, and networking for 5G core functions like UPF, enabling quick provisioning and decoupling of infrastructure from network functions.

Explore virtualization concepts by creating virtual machines that disaggregate hardware from applications, allowing flexible, efficient allocation of processing, memory, and networking for 5G core functions like UPF and AMF.

Convert physical resources into virtual resources with a hypervisor, dynamically allocate RAM across virtual machines, and reveal virtualization benefits like reduced hardware costs, downtime, and faster provisioning.

Learn how virtualization decouples infrastructure from telecom functions and how orchestration automates onboarding, scaling, updating, and unprovisioning of network services to match variable traffic and improve efficiency.

Explore how virtualization converts hardware into virtual compute, network, and storage, with the orchestrator coordinating Wim and Vnf to auto provision resources.

Explore how software defined networking disaggregates data and control planes, enabling a central controller to reroute transport traffic via OpenFlow for better availability and quality of service.

Explore cloud computing as a pay as you go model enabling on-demand access to storage, databases, networking, and analytics hosted publicly or privately.

Provision resources on the cloud on demand, pay for what you use, and scale services with reliable regional availability zones and data replication.

Explore public, private, and hybrid cloud models for telecom operators, balancing resource sharing, virtualization, and regulatory compliance with machine learning and big data.

Explore public, private, and hybrid clouds and differentiate IaaS, PaaS, SaaS, and serverless models, from on-premises data centers to third-party, subscription-based services.

Explore telecom cloud foundations by examining virtualization, software defined networking, and orchestration that deploy and scale RAN and core network functions across private, public, edge, and data center clouds.

Access and download the section resources from the resources folder in the last lecture, then review the documents for future refresher, interviews, or projects.