Sub-Type,Sub-TLV Name,Reference,Comment
0,Reserved,[RFC9041],
1,Multipath data,[RFC8029],
2,Label stack,[RFC8029],
3,FEC stack change,[RFC8029],
4,Local Interface Index,[RFC8611],
5,Remote Interface Index,[RFC8611],
6-31739,Unassigned,,
31740-31743,Reserved for Experimental Use,[RFC9041],"Not to be assigned. This range is for sub-TLVs that require an error message if not recognized. [RFC9041, Section 3.1]"
31744-64507,Unassigned,,
64508-64511,Reserved for Experimental Use,[RFC9041],Not to be assigned. This range is for sub-TLVs that can be silently dropped if not recognized.
64512-65535,Unassigned,,