5G-NR Non-standalone access call flows

These sequence diagrams walk through 5G non-standalone access (EN-DC) — the 4G eNB adding a 5G gNB as a secondary node. Capturing EN-DC setup yourself? VisualEther renders the dual-connectivity signaling from a Wireshark PCAP as a sequence diagram you can read at a glance.

5G-NR non-standalone access (NSA)

Covers the UE registration for dual connectivity followed by the 4G-eNB moving a bearer to the 5G-NR gNB.

5G-NR non-standalone access (with EPC flow)

Adds details on how the EPC deals with dual connectivity subscribers.

5G-NR non-standalone Message Details - HTML

The 5G non-standalone dual connectivity message and action details in HTML format.

5G-NR non-standalone Message Details - PDF

The 5G non-standalone dual connectivity message and action details in PDF format.

UE Role

UE role in 5G Non-standalone access flow.

5G gNodeB role

Role played by the 5G gNodeB as the secondary node in a 4G LTE network.

LTE eNodeB role

LTE eNodeB role setting up 5G Non-Standalone access (EN-DC dual connectivity)

4G Core Network role

Role played by the 4G-EPC in setting up 5G Non-Standalone access.

Summarize the 5G Non-standalone access flow

Review our understanding of the EN-DC dual connectivity flow at a higher level.

Learn about 4G-5G dual connectivity (EN-DC)

Signaling flow for 5G access via LTE-5G NR dual connectivity (EN-DC).