A radio link control (RLC) layer provides RLC entity information to a medium
access
control (MAC) layer. The RLC entity information indicates that the RLC layer has
service data unit (SDU) data to be transmitted. After providing the RLC entity
information, the RLC layer receives an unexpected data interruption that requires
the RLC layer to discard or interrupt transmitting the SDU data. After the unexpected
data interruption, the MAC layer requests at least a protocol data unit (PDU) from
the RLC layer in response to the RLC entity information. The RLC layer then submits
to the MAC layer at least one padding PDU in response to the MAC request. The padding
PDU is submitted in place of the discarded SDU data. Alternatively, the affected
SDU data is not discarded until the next transmission time interval (TTI).
