Within a networking device, packet portions from multiple PDRSDs (Packet Data Receiving and Splitting Devices) are loaded into a single memory, so that the packet portions can later be processed by a processing device. Rather than the PDRSDs managing the storing of packet portions into the memory, a packet engine is provided. The PDRSDs use a PPI addressing mode in communicating with the packet engine and in instructing the packet engine to store packet portions. A PDRSD requests a PPI from the packet engine, and is allocated a PPI by the packet engine, and then tags the packet portion to be written with the PPI and sends the packet portion and the PPI to the packet engine. Once the packet portion has been processed, a PPI de-allocation command causes the packet engine to de-allocate the PPI so that the PPI is available for allocating in association with another packet portion.