Dual Connectivity Handover Security Key Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless telecommunications systems face challenges in efficiently managing handovers between network nodes, particularly for devices with stringent latency and reliability requirements, such as those used in Ultra Reliable and Low Latency Communications (URLLC), due to the break-before-make approach which disrupts uplink data transmission during handovers.
Innovation Solution
Implementing a shared grant-free resource pool for uplink transmissions that is common to both the source and target network access nodes, allowing terminal devices to transmit data using resources selected from this pool during handovers, and facilitating dual connectivity with secure key management to support seamless handover transitions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a break-before-make handover approach is used, then the handover process is simpler to implement, but uplink data transmission is disrupted during handover causing increased latency
Solution Approach 1:
The patent establishes a shared grant-free resource pool in advance that is common to both source and target network access nodes before handover occurs. This preliminary setup allows the terminal device to continuously transmit uplink data without interruption during the handover process, as the resource pool is already prepared and accessible by both nodes.
Solution Approach 2:
The shared grant-free resource pool acts as an intermediary mechanism between the source and target network access nodes. It enables seamless data transmission during handover by providing a common resource pool that both nodes can access, effectively mediating the transition and eliminating transmission gaps.
2Productivity
If grant-based uplink transmission is used during handover, then resource allocation can be controlled, but transmission latency increases due to scheduling requests and grants
Solution Approach 1:
The patent implements grant-free uplink transmission where the terminal device autonomously selects resources from the shared resource pool without requiring scheduling requests or grants from the network. This self-service approach eliminates the latency associated with grant-based scheduling while maintaining resource allocation control through the pre-configured shared pool.
3Reliability
If dual connectivity is implemented for seamless handover, then uplink transmission continuity is maintained, but security key management becomes more complex
Solution Approach 1:
The patent applies different security key management approaches to different connectivity scenarios. When the terminal is connected to the source network access node, the source key is used; when connected to the target node, the target key is used. This localized security management maintains simplicity while supporting dual connectivity for seamless handover.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method of operating a second network access node (206) in a wireless telecommunication system comprising a terminal device (208), a first network access node (204) and the second network access node (206), wherein the method comprises: configuring the second network access node (206) to act as a secondary network access node for a dual connectivity mode of operation for the terminal device (208) in which the first network access node (204) acts as a master network access node, wherein the first network access node (204) is associated with a master network access node security key and the second network access node (206) is associated with a secondary network access node security key, wherein the secondary network access node security key is derived from the master network access node security key and is established by the second network access node (206) from information received from the first network access node (204); establishing, while the second network access node (206) is acting as secondary network access node for the dual connectivity mode of operation for the terminal device (208), that the second network access node (206) should switch to acting as a master network access node for the dual connectivity mode of operation for the terminal device (208); deriving a new master network access node security key to be used by the second network access node (206) when it is switched to acting as a master network access node for the dual connectivity mode of operation for the terminal device (208); and configuring the second network access node (206) to act a master network access node for the dual connectivity mode of operation for the terminal device (208) using the new master network access node security key.