Where is the data for roaming phones stored?

Where is the data for roaming phones stored?

• A. VLR
• B. HLR
• C. IMSI
• D. MME

Answer: (A)

The data needed to support a roaming device is stored where the network can quickly access it as the user moves: the Visitor Location Register. The VLR holds temporary subscriber information for phones that are currently operating in a particular MSC area, including what services are allowed and routing details, so calls and messages can be handled while the user is roaming. When a subscriber roams into a new network, the home location data from the HLR is downloaded to the VLR for that area and retained for the duration of the visit. The HLR stores the permanent subscriber data, IMSI is the subscriber’s identity, and MME handles mobility and session context in LTE, but none of these serve as the roaming data repository in the same way the VLR does.

The data needed to support a roaming device is stored where the network can quickly access it as the user moves: the Visitor Location Register. The VLR holds temporary subscriber information for phones that are currently operating in a particular MSC area, including what services are allowed and routing details, so calls and messages can be handled while the user is roaming. When a subscriber roams into a new network, the home location data from the HLR is downloaded to the VLR for that area and retained for the duration of the visit. The HLR stores the permanent subscriber data, IMSI is the subscriber’s identity, and MME handles mobility and session context in LTE, but none of these serve as the roaming data repository in the same way the VLR does.