Question: What action does the network take to initiate the P-TMSI reallocation procedure, and what information is included in the message sent to the MS?
Option 1: The network sends a P-TMSI REALLOCATION COMPLETE message to the MS, containing only the old P-TMSI combination.
Option 2: The network sends a P-TMSI REALLOCATION COMMAND message to the MS, containing a new combination of P-TMSI, RAI and optionally a P-TMSI signature or a DCN-ID or both allocated by the network.
Option 3: The network sends a P-TMSI REALLOCATION REQUEST message to the MS, without including any P-TMSI information.
Option 4: The network suspends the transmission of user data without sending any message to the MS.
Explanation: When the network initiates the P-TMSI reallocation procedure, it sends a P-TMSI REALLOCATION COMMAND message to the MS. This message includes a new combination of P-TMSI, RAI and optionally a P-TMSI signature or a DCN-ID or both allocated by the network. The network may also suspend the transmission of user data during this procedure.