Patent ID: 8009667

Claim:
A node for use in a communications system that packs and fragments variable-length service data units (SDU) for mapping into variable length protocol data units (PDU), each PDU having a payload area, and a header area, each SDU being associated with a specified connection, the node comprising: a communications processor configured to pack and fragment service data units associated with a specified connection into a protocol data unit, including performing the following operations: allocating bandwidth for the specified connection based, at least in part, on the priority of the connection, establishing a length for the protocol data unit based on the bandwidth allocated to the specified connection in a current frame, mapping a first service data unit to the payload area of the protocol data unit, determining whether a second service data unit is larger than the remaining payload area of the protocol data unit, if the second service data unit is not larger than the remaining payload area of the protocol data unit, then mapping the second service data unit to the remaining payload area of the protocol data unit, and if the second service data unit is larger than the remaining payload area of the protocol data unit, then fragmenting the second service data unit into at least two fragments and mapping the first fragment to the payload area of the protocol data unit, wherein: the header area of the protocol data unit includes a length field specifying the length of the protocol data unit, and the payload area of the protocol data unit includes a packing subheader for each service data unit and each service data unit fragment packed in the payload area, the packing subheader specifying the length of a respective service data unit or a respective fragment.