3Com S7906E Configuration Manual page 723

Figure 1-12 L1/L2 PSNP format
Intradomain routing protocol discriminator
Length indicator
Version/Protocol ID extension
ID length
R R R
Version
Reserved
Maximum area address
PDU length
Source ID
Variable length fields
CLV
The variable fields of PDU comprise multiple Code-Length-Value (CLV) triplets.
CLV format.
Figure 1-13 CLV format
Table 1-2 shows that different PDUs contain different CLVs.
Table 1-2 CLV name and the corresponding PDU type
CLV Code
1 Area Addresses
2 IS Neighbors (LSP)
4 Partition Designated Level2 IS
6 IS Neighbors (MAC Address)
7 IS Neighbors (SNPA Address)
8 Padding
9 LSP Entries
10 Authentication Information
128 IP Internal Reachability Information
129 Protocols Supported
130 IP External Reachability Information
131 Inter-Domain Routing Protocol Information
No. of Octets
1
1
1
1
1
PDU type
1
1
1
2
ID length+1
Name
1-12
Figure 1-13 shows the
PDU Type
IIH, LSP
LSP
L2 LSP
LAN IIH
LAN IIH
IIH
SNP
IIH, LSP, SNP
LSP
IIH, LSP
L2 LSP
L2 LSP