H3C Technologies H3C S12500 Series Switches - Manual (Page 83)

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Figure 30 LSAck packet format
LSA header format
All LSAs have the same header.
Figure 31 LSA header format
Major fields of the LSA header are as follows:
• LS age—Time (in seconds) elapsed since the LSA was originated. An LSA ages in the LSDB (added
by one per second), but does not age in transmission.
• LS type—Type of the LSA.
• Link state ID—The contents of this field depend on the LSA's type.
• Advertising router—ID of the router that originates the LSA.
• 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.
LSAs formats
• Router LSA