CU-UP Change Path Update for Lossless Data Transfer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing CU-UP change procedures in 5G-new radio (NR) base stations face challenges such as the lack of a forwarding path between source and target CU-UP nodes, leading to data packet loss and communication performance degradation during overload conditions.
Innovation Solution
The proposed solution involves an enhanced CU-UP change mechanism that initiates a communication path update to transition from a first data communication path to a second path associated with a target CU-UP node, allowing for lossless data transfer without the need for a forwarding path between nodes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the existing CU-UP change procedure is used, then the system can handle overload conditions by switching CU-UP nodes, but data packet loss occurs due to lack of forwarding path between source and target nodes
Solution Approach 1:
The patent establishes a forwarding path from source CU-UP node to target CU-UP node before the actual CU-UP change occurs. This preliminary action ensures that when data packets need to be forwarded during the transition, the path already exists, preventing packet loss. The forwarding path is set up in advance through coordination between control plane nodes, so that when the user plane function switches, data can be seamlessly redirected without loss.
2Reliability
If the communication path update is delayed until after bearer context modification, then data can be transferred using existing paths, but data packet loss and communication performance degradation occur during overload conditions
Solution Approach 1:
The patent performs the communication path update before the bearer context modification request is communicated. This timing ensures that the forwarding path is already in place when the CU-UP node switch occurs, allowing data to be immediately redirected to the target node without loss. The early execution of path update prevents the performance degradation that would occur if the path were updated after the switch.
Solution Approach 2:
The patent prepares the forwarding path in advance as a cushioning measure against potential data packet loss. By establishing the path before the actual switch occurs, the system creates a safety buffer that absorbs the transition period, ensuring that no packets are lost during the CU-UP node change even under overload conditions.
3Reliability
If data buffering is performed at the source CU-UP node during path transition, then data can be preserved during the switch, but buffering delays data processing and reduces efficiency
Solution Approach 1:
The patent introduces a forwarding path as an intermediary mechanism that allows data to flow directly from the source CU-UP node to the target CU-UP node during the transition. Instead of buffering data at the source node, the forwarding path acts as a mediator that enables continuous data flow. This eliminates the need for buffering while ensuring data preservation, thereby maintaining data processing efficiency without sacrificing reliability.
Data Source
AI summary
Enhanced CU-UP change associated with a device can be performed and managed. CU-CP can trigger transition from source CU-UP to target CU-UP. Before bearer context modification request is communicated from CU-CP to source CU-UP, CU-CP can effectuate communication path update to transition from first uplink path, associated with source CU-UP, DU, and UPF, to second uplink path, associated with target CU-UP, DU, and UPF. Target CU-UP can buffer uplink data until CU-CP receives uplink PDCP count from source CU-UP and forwards that count to target CU-CP. CU-CP or UPF can transition or facilitate transitioning from first downlink path associated with source CU-UP, DU, and UPF, to second downlink path, associated with target CU-UP, DU, and UPF. Target CU-UP can buffer downlink data until CU-CP receives downlink PDCP count from source CU-UP and forwards that count to target CU-CP. Source CU-UP can transfer remaining downlink data it has to DU.