Library /sys$common/syshlp/tcpip$ucp_help.hlb DEFINE, COMMUNICATION_CONTROLLER, Qualifiers, /INTERNET_INTERFACE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /INTERNET_INTERFACE=character

    Required.

    Specifies the first letter of the interface name. The second
    character of the two-character interface name is automatically
    assigned, depending on what you specify for the /TYPE qualifier.
    If you prefer a standard name, call your Compaq support
    representative. If a standard interface name is not important,
    you can use any unique alphabetic character for this first
    character.