mac_address Required. Specifies the physical network adddress (the hardware address) on an FDDI, Ethernet, or Token Ring LAN segment to be mapped to an IP address. For mac_address, specify hh-hh-hh-hh-hh-hh, where hh are pairs of hexadecimal digits. host Required. Specifies the host on the targeted LAN segment. If you do not supply a host name, you must supply its corresponding IP address.