User manual

xStack DES-3800 Series Layer 3 Stackable Fast Ethernet Managed Switch
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Link-State Age
Options Link-State Type
Link-State ID
Advertising Router
Link-State Sequence Number
Link-State Checksum
Length
Routers Links Advertisements
Reserved Reserved Number of Links
Link ID
Link Data
Type No. Of TOS TOS 0 Metric
TOS
Metric
...
TOS
Metric
...
Link ID
Link Data
0
0
VBE
Figure 8- 23. Routers Links Advertisements
In router links advertisements, the Link State ID field is set to the router’s OSPF Router ID. The T -
bit is set in the advertisement’s Option field if and only if the router is able to calculate a separate set
of routes for each IP Type of Service (TOS). Router links advertisements are flooded throughout a
single area only.
Field Description
V - bit When set, the router is an endpoint of an active virtual link that is
using the described area as a Transit area (V is for Virtual link
endpoint).
E - bit When set, the router is an Autonomous System (AS) boundary
router (E is for External).
B - bit When set, the router is an area border router (B is for Border).
Number of Links The number of router links described by this advertisement. This
must be the total collection of router links to the area.
The following fields are used to describe each router link. Each router link is typed. The Type field
indicates the kind of link being described. It may be a link to a transit network, to another router or to