Question: In the derivation of KeNB from KASME in a 3GPP SAE security architecture, what is the purpose of setting the Format Code (FC) to 0x11 in the input S to the Key Derivation Function (KDF)?
Option 1: To indicate the use of a downlink NAS COUNT for KeNB derivation.
Option 2: To signify the establishment of unencrypted E-UTRAN radio bearers.
Option 3: To trigger a key change on-the-fly without bearer re-establishment.
Option 4: To identify the derivation process as being for KeNB from KASME, specifically for cryptographically protected E-UTRAN radio bearers.
Explanation: Setting FC to 0x11 in the input S to the KDF identifies the KeNB derivation process from KASME, applied when establishing cryptographically protected E-UTRAN radio bearers or performing a key change on-the-fly, ensuring secure key management within the 3GPP SAE security architecture.