3Com S7906E - Switch, Configuration Manual

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1-15
Figure 1-16 Router LSA format
Major fields:
z
Link State ID: ID of the router that originated the LSA.
z
V (Virtual Link): Set to 1 if the router that originated the LSA is a virtual link endpoint.
z
E (External): Set to 1 if the router that originated the LSA is an ASBR.
z
B (Border): Set to 1 if the router that originated the LSA is an ABR.
z
# Links: Number of router links (interfaces) to the area, described in the LSA.
z
Link ID: Determined by Link type.
z
Link data: Determined by Link type.
z
Type: Link type. A value of 1 indicates a point-to-point link to a remote router; a value of 2 indicates
a link to a transit network; a value of 3 indicates a link to a stub network; a value of 4 indicates a
virtual link.
z
#TOS: Number of different TOS metrics given for this link.
z
Metric: Cost of using this router link.
z
TOS: IP Type of Service that this metric refers to.
z
TOS metric: TOS-specific metric information.
2) Network LSA
A Network LSA is originated by the DR on a broadcast or NBMA network. The LSA describes all routers
attached to the network.