Question: In the context of Lawful Interception (LI) as per 3GPP security standards, what is the composition of the Network Identifier (NID) in terms of its constituent parts?
Option 1: Only a Network Element Identifier (NEID), which can be an IP address or another unique identifier.
Option 2: Solely an Operator-Identifier (e.g., for NO/AN/SP), ensuring international uniqueness.
Option 3: A combination of two identifiers: (1) a mandatory Operator-Identifier (for NO/AN/SP) and (2) an optional Network Element Identifier (NEID), which may be required based on regional regulations or network type.
Option 4: Neither Operator-Identifier nor NEID; the NID is generated dynamically for each LI operation.
Explanation: The correct composition of the Network Identifier (NID) for Lawful Interception, as outlined in 3GPP security standards, includes both a mandatory unique identifier for the network operator (NO/AN/SP) to ensure international uniqueness and an optional Network Element Identifier (NEID). The NEID's optionality can become a requirement under specific regional regulations (e.g., for GSM and UMTS systems in the U.S.) or based on national mandates, highlighting its conditional necessity.