137
Figure 60
L1/L2 PSNP format
CLV
The variable fields of PDU comprise multiple Code-Length-Value (CLV) triplets.
Figure 61
CLV format
shows that different PDUs contain different CLVs. Code 1 to 10 of CLV are defined in ISO 10589
(code 3 and 5 are not shown in the table), and others are defined in RFC 1195.
Table 5
CLV name and the corresponding PDU type
CLV Code
Name
PDU Type
1
Area Addresses
IIH, LSP
2
IS Neighbors (LSP)
LSP
4
Partition Designated Level 2 IS
L2 LSP
6
IS Neighbors (MAC Address)
LAN IIH
7
IS Neighbors (SNPA Address)
LAN IIH
8 Padding
IIH
9 LSP
Entries
SNP
10
Authentication Information
IIH, LSP, SNP
128
IP Internal Reachability Information
LSP
129
Protocols Supported
IIH, LSP
130
IP External Reachability Information
L2 LSP
131
Inter-Domain Routing Protocol Information
L2 LSP
Intradomain routing protocol discriminator
Reserved
Version
R
ID length
Version/Protocol ID extension
Length indicator
Maximum area address
R
R
PDU type
No. of Octets
1
1
1
1
1
1
1
1
PDU length
Source ID
Variable length fields
2
ID 1