Patent ID: 7668198

Claim:
A method of converting data units (SDU) of an upper layer into data units (PDU) of a lower layer having at least one fixed size, the method comprising: (a) including a data unit (SDU) of the upper layer into a current data unit (PDU) of the lower layer; (b) including a second indicator (LI) into a following data unit (PDU) of the lower layer only when an end of the data unit (SDU) of the upper layer correctly matches the end of the current data unit (PDU) of the lower layer and a first indicator (LI) indicating the end of the data unit (SDU) of the upper layer is not included within the current data unit (P DU) of the lower layer, wherein the second indicator (LI) indicates that the end of the data unit (SDU) of the upper layer correctly matches the end of the current data unit (PDU) of the lower layer, wherein steps (a) and (b) are performed by transmitting side of a communication network for transmission of the current and following data units (PDUs) to a receiving side of the communication network.