Question: What happens to TMSIs and LMSIs associated with a mobile station when the serving VLR (Visitor Location Register) restarts after a failure?
Option 1: They are automatically updated with new values upon VLR restart.
Option 2: They remain valid until the next periodic location update.
Option 3: They become invalid, requiring a 'Provide Roaming Number' or 'Update Location Area' request to restore accuracy.
Option 4: They are temporarily suspended but regain validity after a set time period.
Explanation: Upon VLR restart, all TMSIs (Temporary Mobile Subscriber Identities) and LMSIs (Local Mobile Subscriber Identities) associated with affected mobile stations become invalid. This means these identifiers can no longer be relied upon as accurate until the VLR receives a 'Provide Roaming Number' or an 'Update Location Area' request for the specific mobile station, triggering the restoration of accurate subscriber data.