5G • Core Network
SSC Mode 1
Session and Service Continuity Mode 1
Session continuity mode guaranteeing that the UE's IP address remains strictly unchanged during mobility.
Technical Explanation
In SSC Mode 1 (the default mode for standard broadband and voice), the network preserves the PDU Session Anchor (PSA) UPF regardless of UE mobility. As the UE travels across cities, user plane traffic is tunneled through intermediate UPFs back to the original PSA, guaranteeing that active TCP sessions and IP addresses never break.
Key Functions
- Preserves user IP address indefinitely across geographic mobility
- Tunnels user traffic back to original PDU Session Anchor (PSA)
- Default continuity mode for web browsing, video streaming, and voice calls
Specifications
3GPP TS 23.501
Interfaces
N1N9
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