Network Node Security Key Retention for LTE Handover Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In LTE communication networks, the frequent handover of security keys during handovers between cells leads to processor cycle consumption, memory usage, and delays in encryption and integrity key renegotiation, compromising user experience and increasing implementation complexity and costs.
Innovation Solution
Implementing a mechanism to retain access-stratum keys during handovers, allowing the network to instruct the UE whether to retain or change the keys, with the UE having the option to follow or override this decision based on security policies, ensuring secure key reuse without compromising security.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If security keys are changed during every handover, then security is improved, but processor load and key renegotiation delays increase
Solution Approach 1:
The patent implements dynamic key retention decisions based on handover type. For intra-eNB handovers, the same key is retained to reduce renegotiation overhead, while for inter-eNB handovers, keys are changed to maintain security. This dynamic approach adapts the key management strategy to the specific handover scenario, resolving the contradiction between security and delay.
Solution Approach 2:
The patent applies different key management policies to different handover contexts. Intra-eNB handovers use key retention with local security context, while inter-eNB handovers use key changes. This localized quality approach allows optimization for each specific handover type rather than applying a uniform policy, reducing unnecessary key renegotiation delays while maintaining appropriate security levels.
2Reliability
If security keys are changed during every handover, then security is improved, but processor cycle consumption increases
Solution Approach 1:
The system dynamically determines whether to change or retain security keys based on the handover type. For intra-eNB handovers, the eNB reuses the existing security context and key, avoiding expensive key derivation operations. For inter-eNB handovers, keys are changed as required. This dynamic decision-making reduces unnecessary processor cycles while maintaining security.
Solution Approach 2:
Different key management approaches are applied locally to different handover scenarios. Intra-eNB handovers utilize local security context retention to minimize processing, while inter-eNB handovers perform full key changes. This localized optimization reduces overall processor cycle consumption by avoiding redundant key derivation in appropriate scenarios.
3Reliability
If security keys are changed during every handover, then security is improved, but implementation complexity increases
Solution Approach 1:
The patent introduces dynamic key retention logic that evaluates handover type to determine appropriate key management. The eNB determines whether a handover is intra-eNB or inter-eNB and applies the corresponding key management strategy. This dynamic approach simplifies implementation by providing clear decision rules rather than requiring complex key management in all scenarios.
Solution Approach 2:
The patent applies differentiated key management policies: intra-eNB handovers use simplified key retention with local context, while inter-eNB handovers use standard key changes. This local quality approach reduces implementation complexity by optimizing for each handover type rather than requiring a single complex solution for all cases.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
According to an exemplary aspect, there is provided a method of operating a communication device, the method comprising receiving (121) an indication of whether a first key that is used for encrypting communications on a first radio link with a communication network is to be reused for encrypting communications on a second radio link with the communication network; and if the received indication indicates that the first key is to be reused, determining (123) whether to operate according to the received indication and reuse the first key for encrypting communications on the second radio link.