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5G SA Roaming

Duration : 2 days

Objectives : Understand data and voice roaming architectures in the 5G SA context.

Who should attend : Telecommunications engineer, Telecommunications consultant, Telecommunications architect

Prerequisites : Minimum knowledge of mobile roaming and 5G core network

Course outline : Mobility is the key to the success of mobile networks. Roaming has extended the definition of mobility beyond technology, networks and country borders. The purpose of this training is to present 5G SA roaming through:
• Its architecture.
• Its operating modes: HR and LBO.
• Its interfaces.
• 5G SA roaming procedures; registration, PDU session establishment, sending and receiving SMS over NAS.
• Node addressing and traffic routing
• Security for the signaling exchange between the visited network and the home network
• Data and voice services in 5S SA roaming.

1. Introduction
1.1. Key elements of 5G SA roaming
1.2. Requirements for 5G SA roaming
1.2.1. Functional Architecture Requirements
1.2.2. Security Requirements
1.3. 5GA Architectures for Roaming
1.3.1. For data Home routing virtual home routing Local breakout
1.3.2. For voice N9HR LBO for the emergency call
1.4. Entities for the interconnection of networks in the context of roaming
1.4.1. SEPP
1.4.2. IPX HTTP Proxy
1.4.3. IPX network
1.5. Roaming Hub
1.6. Roaming Sponsor

2. Interfaces for HR and LBO
2.1. HTTP/2 and JSON interfaces for the control plane
2.1.1. N.8. AMF – UDM: LBO & HR
2.1.2. N.10. SMF – UDM: LBO
2.1.3. N.14. AMF – AMF: LBO & HR, for Inter-network mobility
2.1.4. N.12. AMF – AUSF: LBO & HR
2.1.5. N.16. vSMF–hSMF: HR
2.1.6. N.21. SMSF – UDM: LBO & HR
2.1.7. N.24. vPCF – hPCF: LBO & HR
2.1.8. N.27. vNRF – hNRF: LBO & HR
2.1.9. N.31. vNSSF – hNSSF: LBO & HR
2.1.10. N32-c N32-f. SEPP – SEPP: LBO & HR N32-c interface N32-f interface
2.2. GTP-U interfaces for the user plane
2.2.1. N9. vUPF–hUPF: HR

3. 5G SA roaming procedures
3.1. Registration procedure
3.2. PDU session establishment procedure
3.3. Procedure for sending and receiving SMS over NAS

4. Naming, addressing and routing for 5G SA roaming
4.2. Load distribution between SEPPs of visited and home networks
4.3. SEPP FQDN declaration in IR.21 document
4.4. Dynamic discovery of SEPPs via DNS and HTTP redirection
4.5. Telescopic FQDN for communication between NFs of different networks in the context of 5G SA roaming
4.6. Routing by SEPPs according to telescopic FQDNs

5. Security of HTTP/2 traffic between SEPP of the visited network and SEPP of the home network
5.1. Direct TLS architecture between SEPPs in the context of national roaming for example
5.2. PRINS architecture (PRotocol for N32 INterconnect Security) between SEPP via IPX HTTP Proxy (roaming via international carriers)
5.3. Comparison between the two approaches
5.4. TLS and PRINS use case between SEPPs

6. 5GC/EPC interworking in the context of roaming
6.1. Architecture for 5GC/EPC interworking in roaming
6.2. PGW Selection
6.3. 5G/4G or 4G/5G Inter-RAT handover

7. Slicing in 5G SA roaming
7.1. UE support for network slicing in 5G SA roaming
7.2. 5GC support for network slicing in 5G SA roaming
7.3. Use cases of access to network slices by a UE in 5G SA roaming

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