In the SRNC there is one MAC-es entity per UE. Key functions of MAC-es in the SRNC include: – route MAC-es PDU to the correct reordering buffer. – Reordering – this function is responsible for reordering received MAC-es PDU. Each logical channel has its own reordering queue. – Disassembly – this is responsible for disassembly of MAC-es PDU, such that the MAC-d PDU can be delivered to MAC-d. – Macro Diversity Selection – depending on implementation, when an UE is in soft handover there may be one or more reordering queue distribution entities.