Question: In an Evolved Universal Terrestrial Radio Access Network (E-UTRAN), what is the primary purpose of the SN Status Transfer procedure during an X2 handover or dual connectivity scenarios for each respective E-RAB?
Option 1: To transfer uplink/downlink PDCP Sequence Number (SN) and Hyper Frame Number (HFN) status between eNBs to preserve PDCP SN and HFN continuity.
Option 2: To synchronize the radio resource allocation between the source and target eNB for seamless handover.
Option 3: To notify the target eNB about the UE's current RRC state for efficient connection re-establishment.
Option 4: To initiate data forwarding from the source eNB to the target eNB without SN status preservation.
Explanation: The SN Status Transfer procedure ensures continuity of PDCP Sequence Numbers and Hyper Frame Numbers for each E-RAB during handovers or dual connectivity scenarios, maintaining data integrity and preventing errors. This preserves sequence and timing context between old and new base stations (eNBs), ensuring seamless communication continuity for the User Equipment (UE).