Value,Description,Reference
0-9,Unassigned,
10,FS-LSP,[RFC7356]
11,FS-CSNP,[RFC7356]
12,FS-PSNP,[RFC7356]
13-14,Unassigned,
15,L1-LAN-HELLO-PDU,[ISO-10589]
16,L2-LAN-HELLO-PDU,[ISO-10589]
17,P2P-HELLO-PDU,[ISO-10589]
18,L1-LSP-PDU,[ISO-10589]
19,Unassigned,
20,L2-LSP-PDU,[ISO-10589]
21-22,Unassigned,
23,MTU-PROBE-PDU,[RFC7176]
24,L1-CSNP-PDU,[ISO-10589]
25,L2-CSNP-PDU,[ISO-10589]
26,L1-PSNP-PDU,[ISO-10589]
27,L2-PSNP-PDU,[ISO-10589]
28,MTU-ACK-PDU,[RFC7176]
29-31,Unassigned,