H3C Technologies H3C S7500E Series Switches - Manual (Page 83)

4-14
Figure 4-14 LSAck packet format
...
LSA header format
All LSAs have the same header, as shown in the following figure.
Figure 4-15 LSA header format
Major fields:
z LS age: Time in seconds elapsed since the LSA was originated. An LSA ages in the LSDB (added
by 1 per second), but does not age during in transmission.
z LS type: Type of the LSA.
z Link State ID: The contents of this field depend on the LSA's type
z LS sequence number: Used by other routers to judge new and old LSAs.
z LS checksum: Checksum of the LSA except the LS age field.
z Length: Length in bytes of the LSA, including the LSA header.
Formats of LSAs
1) Router LSA