Aviz details Service Node for 4G and 5G subscriber visibility
Aviz Service Node maintains continuous subscriber visibility across 4G Evolved Packet Core (EPC) and 5G core during inter-RAT handovers by passively detecting and correlating sessions in real time, performing in-place upgrades and exporting updated metadata without affecting live traffic.
Research overview
Mobile operators transitioning to mixed 4G and 5G deployments face loss of control plane session context when subscribers move between radio technologies. Aviz describes a passive observability layer that links control and user plane data to preserve session continuity across Evolved Packet Core (EPC) and 5G Core Network (5GC) interfaces.
Key findings
The Service Node uses IMSI-based matching to identify related session records and applies in-place session upgrade logic so a handover appears as a continuation rather than a new session. Metadata reflecting updated session state is streamed in real time to Kafka, and the solution operates without introducing traffic into live network paths.
Technical breakdown
Passive operation and data sources
The node consumes mirrored signaling from control plane interfaces and mirrored user plane traffic from N3, N4, and S1‑U, enabling observability without active insertion into live flows.
Correlation and session upgrade
Incoming requests are validated against existing EPC and 5GC contexts and, when appropriate, reclassified as handovers rather than new sessions to retain end-to-end traceability.
Metadata export and interfaces
Normalized and enriched subscriber metadata is exported to Kafka so analytics and monitoring tools receive synchronized session data across S11, N11, S1‑U, N3, and N4 interfaces.
Operation without network changes
The Service Node functions without modifications to mobility procedures or control plane configuration, preserving current network operations while adding correlated observability.
Operational impact
Maintaining linked control and user plane contexts reduces blind spots that occur during inter‑RAT transitions and supports faster resolution of handover and tunnel mismatch issues. The approach preserves continuity for KPIs such as latency, packet loss, and handover success rate while enabling unified analytics across EPC and 5GC domains.
Product update
Aviz Service Node detects subscriber movement between Long Term Evolution (LTE) and 5G, identifies relevant control and user plane interfaces, and performs in-place session upgrades to maintain a unified subscriber view. The system exports updated metadata for downstream analytics without requiring reconfiguration of existing network elements.
This