Planet Networking & Communication WGS3-24000 User Manual page 235

4.6.4.9 OSPF Link State Database
Non-Configurable Data
。 Router ID - The 32 bit integer in dotted decimal format that uniquely identifies the router within the autonomous
system (AS). The Router ID is set on the IP Configuration page. If you want to change the Router ID you must first
disable OSPF. After you set the new Router ID, you must re-enable OSPF to have the change take effect. The
default value is 0.0.0.0, although this is not a valid Router ID.
。 Area ID - The ID of an OSPF area to which one of the router interfaces is connected. An Area ID is a 32 bit integer in
dotted decimal format that uniquely identifies the area to which an interface is connected.
。 LSA Type - The format and function of the link state advertisement. One of the following:
Router Links
Network Links
Network Summary
ASBR Summary
AS-external
LS ID - The Link State ID identifies the piece of the routing domain that is being described by the
advertisement. The value of the LS ID depends on the advertisement's LS type.
Age - The time since the link state advertisement was first originated, in seconds.
Sequence - The sequence number field is a signed 32-bit integer. It is used to detect old and duplicate
link state advertisements. The larger the sequence number, the more recent the advertisement.
Checksum - The checksum is used to detect data corruption of an advertisement. This corruption can
occur while an advertisement is being flooded, or while it is being held in a router's memory. This field is
the checksum of the complete contents of the advertisement, except the LS age field.
Figure 4-6-26 OSPF Link State Database
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