Method and apparatus for transmitting data packets and method and apparatus for receiving data packets

An apparatus for transmitting a data packet having a header and a payload, comprising:

• one or more computing devices to:
• configure the payload to transport at least one full service data unit, one or two service data unit fragments, or at least one full service data unit and at least one service data unit fragment, where a service data unit fragment is only located (i) at the beginning of the data packet payload or at the end of the data packet payload or (ii) at the beginning of the data packet payload and at the end of the data packet payload;
• configure an indicator in the header consisting of a first bit and a second bit even when a number of full service data units and service data unit fragments in the payload is more than two, the indicator indicating whether (i) the data packet payload begins with a fragment of a service data unit and (ii) the data packet payload ends with a service data unit fragment;
• and
• form the data packet including the configured header and the configured payload;
• and
• a transmitter to transmit the data packet.

A method for receiving a data packet, comprising steps of:

• receiving the data packet that includes a data packet header and a data packet payload,
• the data packet header including an indicator consisting of a first bit and a second bit even when a number of full service data units and service data unit fragments in the data packet payload is more than two, the indicator indicating whether (i) the data packet payload begins with a fragment of a service data unit and (ii) the data packet payload ends with a service data unit fragment;
• and
• the data packet payload including at least one full service data unit, one or two service data unit fragments, or at least one full service data unit and at least one service data unit fragment, where a service data unit fragment is only located (i) at the beginning of the data packet payload or at the end of the data packet payload or (ii) at the beginning of the data packet payload and at the end of the data packet payload;
• and
• restructuring service data unit(s) and/or service data unit fragment(s) in the received data packet based on the indicator.

An apparatus for receiving a data packet, comprising:

• a receiver to receive the data packet that includes a data packet header and a data packet payload,
• the data packet header including an indicator consisting of a first bit and a second bit even when a number of full service data units and service data unit fragments in the data packet payload is more than two, the indicator indicating whether (i) the data packet payload begins with a fragment of a service data unit and (ii) the data packet payload ends with a service data unit fragment;
• and
• the data packet payload including at least one full service data unit, one or two service data unit fragments, or at least one full service data unit and at least one service data unit fragment such that a service data unit fragment is only located (i) at the beginning of the data packet payload or at the end of the data packet payload or (ii) at the beginning of the data packet payload and at the end of the data packet payload;
• and
• one or more computing devices to restructure service data unit(s) and/or service data unit fragment(s) in the received data packet based on the indicator. The apparatus for receiving a data packet according to claim 10, wherein the first bit indicates whether the data packet payload begins with a service data unit fragment and the second bit indicates whether the data packet payload ends with a service data unit fragment.