Ethernet II + IPv4 + UDP Frame Structure Reference
When implementing a network interface in RTL, you need a precise byte-offset map for every field in the frame. This post provides that reference for the most common combination: Ethernet II + IPv4 + UDP. Layer Stack [ Preamble (7B) + SFD (1B) ] ← handled by PHY/MAC, not in user datapath [ Ethernet II header ] [ IPv4 header ] [ UDP header ] [ Application data ] [ FCS / CRC-32 (4B) ] ← often stripped/added by MAC IP (configurable option in Xilinx TEMAC / Tri-MAC) Note: The preamble, SFD, and inter-packet gap (IPG) are inserted and stripped by the PHY/MAC layer and are typically not visible in the AXI-Stream user interface of a MAC IP core. ...