Question: What is the primary purpose of the SGNB Modification Request message sent from the Master eNodeB (MeNB) to the secondary gNodeB (en-gNB) in an E-UTRAN architecture?
Option 1: To initiate handover of a User Equipment (UE) from the en-gNB to the MeNB.
Option 2: To request the en-gNB to release resources allocated for a specific UE due to inactivity.
Option 3: To prepare modification of en-gNB resources for a UE, query the current Secondary Cell Group (SCG) configuration, or provide Serving Cell Radio Link Failure (S-RLF)-related information.
Option 4: To synchronize the MeNB and en-gNB for simultaneous transmission to a UE in Coordinated Multi-Point (CoMP) operation.
Explanation: The correct answer, Option 3, aligns with the extracted text's description of the SGNB Modification Request message's purpose. This message is utilized for three key reasons: 1. Resource Modification Preparation: Ensuring the en-gNB is ready to adjust its resource allocation for a specific UE. 2. SCG Configuration Query: Allowing the MeNB to understand the current configuration of the Secondary Cell Group at the en-gNB. 3. Providing S-RLF Information: Sharing details related to Serving Cell Radio Link Failure with the en-gNB, which is crucial for maintaining seamless connectivity and managing potential link failures effectively. This multifaceted approach highlights the message's importance in E-UTRAN's operational efficiency and UE service continuity.