Subscriber Deregistration via Time Supervision in Mobile Networks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing Location Update and deregistration procedures in GSM/3GPP mobile networks face instability and capacity issues due to lost signaling messages, particularly when roaming across different networks, leading to non-unique subscriber registrations and incorrect location information.
Innovation Solution
A method and system for deregistering user equipment from a source control node involve receiving an identification request, starting a time supervision for a cancel location message, and deregistering the equipment when the supervision expires, ensuring timely and reliable de-registration even if cancel location messages are lost in intermediate networks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the cancel location message is sent through intermediate networks during roaming, then the subscriber location can be updated in the target MSC, but the message may be lost causing the subscriber to remain registered in the source MSC
Solution Approach 1:
The source MSC proactively deregisters the UE before the cancel location message is expected to arrive. When the source MSC receives an identification request from the target MSC, it immediately initiates deregistration of the UE, rather than waiting for the cancel location message. This preliminary action ensures that even if the cancel location message is lost in intermediate networks, the subscriber registration is properly cleaned up from the source MSC, preventing duplicate registrations and maintaining network consistency.
2Measurement precision
If the source MSC waits for the cancel location message before deregistering the UE, then accurate location information is maintained, but network stability is compromised when messages are lost
Solution Approach 1:
The source MSC performs deregistration as a preliminary action upon receiving the identification request, before the cancel location message is expected to arrive. This approach prioritizes network stability by ensuring deregistration happens even if the cancel location message is lost, while the identification request itself provides sufficient information to maintain location accuracy.
Solution Approach 2:
The identification request message from the target MSC serves as feedback that triggers the deregistration process. This feedback mechanism allows the source MSC to respond proactively to location update events, initiating deregistration based on the identification request rather than passively waiting for the cancel location message, thereby improving network stability while maintaining location information accuracy.
3Device complexity
If the subscriber remains registered in both source and target MSC due to message loss, then no deregistration action is taken, but capacity and subscription issues arise in MSCs
Solution Approach 1:
The source MSC performs preliminary deregistration upon receiving the identification request, ensuring that the UE is removed from the source MSC registration before the cancel location message arrives. This prevents the UE from being registered in both source and target MSC simultaneously, thereby preventing capacity and subscription issues while maintaining simple registration management through the identification request trigger.
Data Source
AI summary
A system, methods, node, and non-transitory computer readable medium storing a computer program, for deregistration of a user equipment from the source control node are described. The user equipment is registered in the source control node and in a subscriber database while roaming from the source control node to a target control node. The method in the source control node comprises receiving an identification request message from the target control node, the identification request requesting identification and security related information. The method in the source control node further comprises, as triggered by the identification request message, starting a time supervision supervising reception of a cancel location message from the subscriber database. When the time supervision expires, the user equipment is deregistered from the source control node.