Efficient memory allocation in a wireless transmit/receiver unit

A method (400) for sharing memory of a unit of wireless transmit / receive (hereinafter WTRU), comprising: transmitting from the WTRU to a corresponding access network radio a signal indicating a size interim storage related to a effective amount of a temporary storage of a control radio link (hereinafter RLC), and a temporary storage reordering access control medium (hereinafter MAC), in which the size of the physical memory Real in that WTRU may be less than the effective sum; receiving (401) in the WTRU one protocol data unit stratum MAC (hereinafter MAC PDU), identified by a sequence number transmission (hereinafter TSN), the MAC PDU comprising one or more RLC PDUs as sub-units each one of which has a sequence number (hereinafter SN) unique underidentification; save that MAC PDU received in a memory location of said memory and processing said MAC PDU in unprimer process based on said unique identification; and treating (445) said RLC PDUs in a second process in accordance with the respective SNs; wherein said MAC PDU and its RLC PDUs are kept in the same memory location throughout the first and second processes.