The NDIS_TCP_SEND_OFFLOADS_SUPPLEMENTAL_NET_BUFFER_LIST_INFO structure contains additional out-of-band information for encapsulated packets. For more information, see Network Virtualization using Generic Routing Encapsulation (NVGRE) Task Offload (NVGRE-TO).


  union {
    struct {
      ULONG IsEncapsulatedPacket  :1;
      ULONG EncapsulatedPacketOffsetsValid  :1;
      ULONG InnerFrameOffset  :8;
      ULONG TransportIpHeaderRelativeOffset  :6;
      ULONG TcpHeaderRelativeOffset  :10;
      ULONG IsInnerIPv6  :1;
      ULONG TcpOptionsPresent  :1;
      ULONG Reserved  :4;
    } EncapsulatedPacketOffsets;
    PVOID Value;



The members of NDIS_TCP_SEND_OFFLOADS_SUPPLEMENTAL_NET_BUFFER_LIST_INFO are meaningful if and only if TcpIpChecksumNetBufferListInfo or TcpLargeSendNetBufferListInfo is specified in the NDIS_NET_BUFFER_LIST_INFO structure.

If the IsEncapsulatedPacket member is TRUE and the TcpIpChecksumNetBufferListInfo out-of-band (OOB) information is valid, this indicates that NVGRE support is required and the NIC must compute the checksum for the tunnel (outer) IP header, the transport (inner) IP header, and the TCP or UDP header if one of them is present. An NVGRE packet will only be offloaded if the packet conforms to miniport-advertised capabilities. For example, a packet containing a UDP header will not be offloaded if the miniport did not advertise UDP Tx checksum offload support in its base capabilities. For more information, see Offloading Checksum Tasks.


Windows version Supported in NDIS 6.30 and later. Supported in NDIS 6.30 and later.
Header ndis.h

See Also



Offloading Checksum Tasks

Network Virtualization using Generic Routing Encapsulation (NVGRE) Task Offload

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