Defines the authority bits that must be set in packets
received via this interface. This is a bit map. Zero is
valid. Authorities have been defined for the first octet.
This is represented by the following 'bit mask' values.
IP_NWIF_AUTH_NONE 0 (0x00)
IP_NWIF_AUTH_GENSER 128 (0x80)
IP_NWIF_AUTH_SIOPESI 64 (0x40)
IP_NWIF_AUTH_SCI 32 (0x20)
IP_NWIF_AUTH_NSA 16 (0x10)
IP_NWIF_AUTH_DOE 8 (0x08)
IP_NWIF_AUTH_ALL 248 (0xF8)
If no value is specified, the software will default to
IP_NWIF_AUTH_NONE.