CIoT Registration Reject Cause Value Guidance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems face challenges in efficiently handling registration requests from user equipment (UE) due to Cellular Internet of Things (CIoT) feature incompatibility, leading to increased attachment time and undefined UE behavior, as the registration reject message does not provide sufficient cause values to guide the UE to suitable networks.
Innovation Solution
Incorporating specific cause values in the registration reject message to direct the UE to select alternative PLMNs or TAs that support its CIoT features, such as cause value #15 for 'no suitable cells' or 'requested EPS optimization not supported', to reduce backward compatibility issues and development efforts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If the registration reject message does not include specific cause values for CIoT feature incompatibility, then the message structure remains simple and backward compatible, but the UE cannot efficiently identify suitable networks leading to increased attachment time and undefined UE behavior
Solution Approach 1:
The registration reject message is segmented to include a specific cause value field that identifies CIoT feature incompatibility. This segmentation allows the message to carry additional information about the rejection reason without fundamentally changing the overall message structure, enabling UEs to efficiently identify suitable networks while maintaining a manageable message format.
Solution Approach 2:
The solution adds a new dimension to the registration reject message by incorporating cause value information that was previously absent. This dimensional addition provides UEs with critical guidance for network selection without requiring a complete restructuring of the message framework, thus reducing attachment time while controlling complexity growth.
2Reliability
If the registration reject message includes specific cause values to guide UE to suitable networks, then UE behavior becomes well-defined and attachment efficiency improves, but the message structure becomes more complex and may cause backward compatibility issues
Solution Approach 1:
The registration reject message structure is designed with universality in mind, where the cause value field can serve multiple functions. It can indicate general rejection reasons for legacy UEs and specifically indicate CIoT feature incompatibility for CIoT-aware UEs. This multi-functionality ensures that the enhanced message structure benefits current UEs while maintaining compatibility with legacy devices that interpret the same message structure.
3Productivity
If the core network entity rejects registration requests due to CIoT feature incompatibility without providing cause values, then the network maintains simplicity in processing, but UEs continue to attempt attachment to incompatible networks increasing system inefficiency
Solution Approach 1:
The core network entity performs preliminary action by including cause value information in the registration reject message before the UE can attempt further attachment to incompatible networks. This preliminary provision of rejection reasons enables UEs to make informed decisions about network selection in advance, preventing wasted attachment attempts and improving overall system efficiency with minimal additional processing complexity.
Data Source
Figure 1
Figure 2A~2D
Figure 3
AI summary
In one aspect, a method, a computer-readable medium, and an apparatus for wireless communication are provided. The apparatus may receive a registration request including requested features by a UE. The apparatus may determine to reject the registration request based on the requested CIoT optimization features. The apparatus may select a cause value from a plurality of cause values to include in a registration reject message to the UE. The apparatus may send the registration reject message to the UE.