Mobile Application Testing

By:-Jayaprakash Narayan (Guest Blogger)

Questions: How the mobile service providers know whether the mobile is switched off or out of coverage?

Answer: When the mobile is voluntarily switched OFF by the user, the mobile sends the Registration message with ‘Inactive’ state, which is update in the MSC/VLR & subsequently HLR… in other words, the network is updated with the device’s inactive status (that’s why it takes a few seconds for your mobile to turn off when you press the standby key)… and the “switched off” message is generated/played by the network to the caller.

When mobile is out of network coverage and/or battery is removed, the mobile doesn’t send (or does not initiate or have time) the registration message… in this case, the HLR & MSC/VLR (network) still has the mobile as “Active” in their register and when the incoming call is routed and the mobile is not reached by the network, the “unreachable” or “out of coverage” message is generated/played by the network.