The LTE packet frame structure is similar to other OSI models. The figure here illustrates the decomposition of the packet from PHY up to the IP layer. The IP packet is enveloped in the 4G-LTE layers:
4G-LTE Packet Structure. IP packets are reformed in the PDCP SDUs and flow through the RLC, MAC, and PHY layers. The PHY creates slots and sub-frames of transport blocks from the MAC layer.
