Question: What is a requirement for a Universal Integrated Circuit Card (UICC) in relation to Generic Bootstrapping Architecture (GBA)?
Option 1: The UICC must only store the NAF_ID provided during manufacturing and cannot be updated.
Option 2: The UICC shall implement GBA_U and be capable of deriving Ks_local from Ks_int_NAF, with the flexibility to apply local policies for key establishment restrictions.
Option 3: The UICC is not required to store any NAF_ID but must support OTA commands for potential future updates.
Option 4: The implementation of GBA_U on the UICC is optional and dependent on the home operator's network configuration.
Explanation: This option correctly reflects the requirements. Implementing GBA_U and deriving Ks_local from Ks_int_NAF are mandatory, while also highlighting the UICC's capability to enforce local policies for restricting key establishment.