H3C Technologies H3C S7500E Series Switches - Manual (Page 157)

5-12
Figure 5-11 L1/L2 CSNP format
PSNP only contains the sequence numbers of one or multiple latest received LSPs. It can
acknowledge multiple LSPs at one time. When LSDBs are not synchronized, a PSNP is used to
request new LSPs from neighbors.
Figure 5-12 shows the PSNP packet format.
Figure 5-12 L1/L2 PSNP format
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 length+1
CLV
The variable fields of PDU comprise multiple Code-Length-Value (CLV) triplets. Figure 5-13 shows the
CLV format.