Bit,Description,Reference
0,Overload Bit (O-bit),[RFC9552]
1,Attached Bit (A-bit),[RFC9552]
2,External Bit (E-bit),[RFC9552]
3,ABR Bit (B-bit),[RFC9552]
4,Router Bit (R-bit),[RFC9552]
5,V6 Bit (V-bit),[RFC9552]
6-7,Unassigned,