DOI Value,Organization or Use,Reference
0:0:0:0,Null DOI.  This ought not be used on any network.,[RFC5570]
0:0:0:1 - 0:255:255:255,For private use among consenting parties within private networks,[RFC5570]
1:0:0:0 - 254:255:255:255,Unassigned,
255:0:0:0 - 255:255:255:255,Reserved to the IETF for future use,[RFC5570]