Question: What is the primary reason for incorporating the BEARER identifier in generating keystreams for encryption in a telecom network?
Option 1: To enable the use of different cipher keys for each user equipment (UE) simultaneously connected to the network.
Option 2: To prevent the reuse of keystreams across multiple radio bearers associated with a single User Equipment (UE) on the same physical layer frame.
Option 3: To reduce computational overhead by generating a single keystream for all bearers of a UE.
Option 4: To comply with regulatory requirements for encryption key management in wireless communications.
Explanation: Incorporating the BEARER identifier in keystream generation ensures that even if the same cipher key is used for different radio bearers of a single user (which are multiplexed onto one physical layer frame), each bearer will have a unique keystream. This prevents potential security vulnerabilities from using the same keystream for more than one bearer, enhancing the security of data transmission over the telecom network.