Question: In an LWA (LWIP - WiFi Interworking) scenario, when a UE (User Equipment) triggers an LWA status report, how does it set the HRW (Highest Received WLAN PDCP Sequence Number) field if no PDCP SDUs have been received on WLAN?
Option 1: Set the HRW field to the PDCP SN of the last successfully transmitted PDCP SDU over E-UTRA.
Option 2: Set the HRW field to the value of the FMS (First Missing PDCP Sequence Number) field.
Option 3: Set the HRW field to a predefined default value indicating no WLAN reception.
Option 4: Do not include the HRW field in the status report.
Explanation: According to the specifications, when triggering an LWA status report and no PDCP SDUs have been received on WLAN, the UE sets the HRW field to the FMS (First Missing PDCP Sequence Number) value. This ensures consistency in reporting even in the absence of WLAN receptions, facilitating accurate sequence number management between E-UTRA and WLAN transmissions.