UDM Subscription
The AMF validates the parameters for RAT Restrictions, Core Network Type Restrictions, and Local Cause Code Mapping. The AMF performs these activities, when it receives the subscription data as am-data. The AMF checks whether the UE is allowed or any enforcement is applicable.
The UDM provides RAT and Core Network Type restrictions in subscription data during and after registration.
When the requested data is modified, the UDM notifies the registered AMF subscribers. The AMF sends the modified mobility list to the UE. If the subscriber is already registered, the AMF continues to serve the UE or deregister based on the updated restrictions.
UDM subscription data configures the AMF with restrictions using RAT type restrictions or local configuration in the Call Control Policy. When the UDM provides the restrictions, the AMF uses and enforces them accordingly. When the UDM doesn't provide restrictions, the AMF uses and implements the available local policy configuration from the Call Control Policy based restriction.
On receiving the updated subscription data and am-data change notification from UDM, the AMF performs the following:
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Processes the data change notifications
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Saves the RAT and Core Network values in the UE context
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Applies the enforcements, if applicable
Note | UE rejects the call at any time during a restriction. During an emergency registration, the AMF doesn't check the restrictions. |
The following subfeatures are associated with this feature: