Splitting Frames at the UDP Payload

NDIS miniport adapters that support header-data split must support splitting frames at the upper-layer-protocol header for UDP frames. However, the NIC must first try to split the frame at the beginning of UDP payload.

The NIC might not be able to split a UDP frame if the resulting header buffer has a greater length than the maximum header size. For more information about splitting frames when the maximum header size is exceeded, see Allocating the Header Buffer.

If the NIC cannot split the frame at the UDP payload, the NIC should split the frame at the beginning of the upper-layer-protocol header or should not split the frame. For more information about splitting frames at the beginning of the upper-layer-protocol header, see Splitting Frames at the Beginning of the Upper-Layer-Protocol Headers.

If the header-data split provider splits the frame at the UDP payload, the indicated NET_BUFFER_LIST structures must have the NDIS_NBL_FLAGS_IS_UDP and NDIS_NBL_FLAGS_SPLIT_AT_UPPER_LAYER_PROTOCOL_PAYLOAD flags set in the NblFlags member. For more information about setting header-data split NET_BUFFER_LIST flags, see Setting NET_BUFFER_LIST Information.