2001-05-01 In the FTP Operation Over Big Address Records (FOOBAR) Protocol there is a field, called "address family" or "af", to identify the lower level protocol addresses in use. This is an 8 bit field. The first 16 assignments (0-15) of the af value are exactly the same as the IP Version number. The assignment for values 16-255 are listed here. IANA assignment 16 IPX Novell IPX 17-254 Unassigned 255 Reserved