UE Multi-Connectivity SN Addition Failure Handling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In next-generation wireless networks, particularly 5G, User Equipment (UE) configured with multi-connectivity often faces challenges in successfully adding a Secondary Node (SN) due to SN addition failures, which hampers the establishment of reliable data paths and service continuity.
Innovation Solution
The proposed solution involves a UE that receives an RRC message with SCG DRB configuration, initiates a timer, and upon specific conditions being met, transmits an RRC reestablishment request or SCG Failure Information message to the Master Node (MCG), allowing for the successful addition of an SCG based on the DRB configuration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a UE attempts to add a Secondary Node (SN) in multi-connectivity configuration, then data capacity and service support are improved, but SN addition failures occur导致 service continuity deteriorates
Solution Approach 1:
The UE performs preliminary actions by starting a timer upon receiving SCG DRB configuration and proactively monitoring addition status. Before failure occurs, the UE prepares to detect addition failure conditions and has the mechanism ready to report failures timely, preventing service interruption
Solution Approach 2:
The UE implements feedback mechanism by monitoring SCG addition status and transmitting SCG Failure Information messages to the MCG when failure conditions are met. This feedback loop enables the network to detect and respond to addition failures, maintaining service continuity despite the initial contradiction
2Measurement precision
If the UE monitors SCG addition status continuously, then failure detection accuracy is improved, but signaling overhead and processing complexity increase
Solution Approach 1:
The UE applies local quality by implementing targeted monitoring only for specific failure conditions rather than continuous comprehensive monitoring. The timer-based mechanism focuses detection resources on critical events (timer expiry, RLF, SCG deactivation), reducing overall processing complexity while maintaining detection accuracy for relevant failures
Solution Approach 2:
The UE changes monitoring parameters dynamically by starting/stopping timers based on configuration reception and failure detection. This parameter-based control (timer values, condition thresholds) enables accurate failure detection without requiring continuous high-complexity monitoring, balancing precision and complexity
3Loss of time
If the UE transmits failure information immediately upon detection, then service recovery time is reduced, but signaling message frequency increases
Solution Approach 1:
The UE extracts and reports only essential failure information (SCG Failure Information message with specific failure causes) rather than transmitting all possible status updates. This selective information extraction reduces signaling overhead while ensuring critical recovery data is communicated promptly, addressing the time-recovery versus signaling-frequency contradiction
Data Source
AI summary
A User Equipment (UE) and a method performed by the UE for multi-connectivity are provided. The method includes receiving, from a Master Cell Group (MCG), a first Radio Resource Control (RRC) message comprising at least one Secondary Cell Group (SCG) Data Radio Bearer (DRB) configuration; starting a first timer upon receiving the first RRC message; and stopping the first timer when one of a plurality of conditions is satisfied, wherein the plurality of conditions include: transmitting an RRC reestablishment request message to the MCG; transmitting an SCG Failure Information message to the MCG before the first timer expires; and successfully adding an SCG based on the at least one SCG DRB configuration.