HP 4800G Series Configuration Manual page 449

Figure 1-14 LSAck packet format
LSA header format
All LSAs have the same header, as shown in the following figure.
Figure 1-15 LSA header format
Major fields:
LS age: Time in seconds elapsed since the LSA was originated. A LSA ages in the LSDB (added
by 1 per second), but does not in transmission.
LS type: Type of the LSA.
Link State ID: The contents of this field depend on the LSA's type
LS sequence number: Used by other routers to judge new and old LSAs.
LS checksum: Checksum of the LSA except the LS age field.
Length: Length in bytes of the LSA, including the LSA header.
Formats of LSAs
1) Router LSA
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