ftp://ftp.microsoft.com/developr/drg/WinSock/MS-Extensions/vxdtdi.zip

    VxD Interface for Wolverine

    This file contains the include files necessary to do development of 
    ring 3 components in Windows for Workgroups 3.11 and Windows 95 
    that talk directly to Microsoft's 32 bit ("Wolverine") TCP/IP stack. 
    These files are unsupported, and provided as an assistance for the 
    advanced programmer. This file will soon be moved to 
    ftp://ftp.microsoft.com/bussys/winsock/ms-ext/.

ftp://ftp.microsoft.com/developr/drg/WinSock/MS-Extensions/wshvxd.zip

    VxD Interface for Winsock helper DLLs

    This file contains the include files necessary to do development of 
    ring 3 components in Windows 95 that bind a third party stack to
    Microsoft's 32 bit Winsock DLL. These files are unsupported, and
    provided as an assistance for the advanced programmer.