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5G/6G AcademyEst. 2009
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Level 9

Voice over 5G (VoNR & IMS)

Deep-dive into Voice over New Radio — IMS architecture and SIP signaling, P-CSCF/I-CSCF/S-CSCF roles, IMS registration, VoNR mobile-originated and mobile-terminated call flows, QoS for voice (5QI=1), EPS Fallback, VoNR-to-VoLTE handover, video calling, and call-quality troubleshooting with MOS analysis.

10 interactive0 simulation3 labs2 quizzes
0/15 lessons

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IMS Architecture for 5G

0/6

Understand the IP Multimedia Subsystem integrated with 5G Core — SIP signaling, CSCF roles (P/I/S-CSCF), TAS, MGCF, IMS registration over 5G, and how IMS and 5GC interwork.

IMS in 5G: architecture and role of each component
Full IMS architecture integrated with 5G Core — P-CSCF, I-CSCF, S-CSCF, TAS, MGCF, and their interfaces to AMF, SMF, PCF, and UPF.
interactive3 min
SIP protocol basics for telecom
Session Initiation Protocol fundamentals — SIP INVITE, 200 OK, ACK, BYE message structure, header fields, and SDP body for media negotiation.
interactive3 min
P-CSCF, I-CSCF, S-CSCF, TAS, MGCF
Role of each IMS entity — P-CSCF as first contact proxy, I-CSCF for interrogation, S-CSCF as session controller, TAS for telephony services, MGCF for PSTN interworking.
interactive3 min
IMS registration over 5G
Animated call flow — UE sends SIP REGISTER through P-CSCF → I-CSCF → S-CSCF, IMS-AKA authentication challenge, and 200 OK registration response.
interactive3 min
Lab: Build IMS + 5GC integrated architecture
Topology exercise — place IMS components (P-CSCF, I-CSCF, S-CSCF, TAS) alongside 5GC NFs (AMF, SMF, UPF, PCF) and connect them with correct interfaces.
lab5 min
Quiz: IMS Architecture
Test your knowledge of IMS components, SIP signaling, CSCF roles, and IMS-5GC integration.
quiz3 min

VoNR Procedures

0/9

Master VoNR call flows — mobile-originated and mobile-terminated setup, dedicated QoS flow (5QI=1), EPS Fallback when NR is unavailable, VoNR-to-VoLTE handover, video calling QoS, and MOS-based call quality analysis.

VoNR call setup — Mobile Originated (MO)
Full MO call flow — SIP INVITE through P-CSCF/S-CSCF/TAS, dedicated QoS flow (5QI=1) via PCF/SMF, media plane through UPF to far end.
interactive3 min
VoNR call setup — Mobile Terminated (MT)
Full MT call flow — incoming SIP INVITE at S-CSCF, paging the idle UE through AMF, QoS flow setup, and media path establishment.
interactive3 min
QoS for voice: 5QI=1 and dedicated QoS flow
How the dedicated voice QoS flow is established — 5QI=1 parameters (100ms PDB, 10⁻² PER), PCF policy rules, SMF QoS flow, gNB DRB mapping.
interactive3 min
EPS Fallback: when VoNR isn't available
What happens when VoNR is unavailable — NR-to-LTE redirection, IMS re-registration on 4G, and VoLTE call setup as fallback.
interactive3 min
VoNR to VoLTE handover during a call
Inter-RAT handover animation — live VoNR call handing over from 5G NR to 4G LTE, bearer mapping, IMS session continuity, and media rerouting.
interactive3 min
Video calling over NR
How video calling adds a second QoS flow (5QI=2, 150ms PDB) alongside voice (5QI=1) — dual-flow setup through PCF and SMF.
interactive3 min
Real-world: VoNR call quality troubleshooting
MOS score analysis, jitter, delay, packet loss — diagnosing VoNR quality issues with EVS and AMR-WB codecs.
lab3 min
Lab: Trace a VoNR call end-to-end
Hands-on exercise — trace a VoNR call from SIP signaling through IMS, QoS flow setup in 5GC, to media path through RAN and UPF.
lab5 min
Quiz: VoNR Procedures
Test your knowledge of VoNR call flows, QoS, EPS Fallback, handover, video calling, and call quality metrics.
quiz3 min