D-Link DES-6500 - Switch User Manual page 163

Router Links Advertisements
Router links advertisements are type 1 link state advertisements. Each router in an area originates a routers links advertisement.
The advertisement describes the state and cost of the router's links to the area. All of the router's links to the area must be
described in a single router links advertisement.
The format of the Router Links Advertisement is shown below:
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
V - bit
E - bit
B - bit
Number of Links
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 a stub network. The values of all the other fields describing
a router link depend on the link's Type. For example, each link has an associated 32-bit data field. For links to stub networks, this
field specifies the network's IP address mask. For other link types, the Link Data specifies the router's associated IP interface
address.
xStack DES-6500 Modular Layer 3 Chassis Ethernet Switch User Manual
Routers Links Advertisements
Link-State Age
Link-State Checksum
V E B
Reserved Reserved
Type No. Of TOS
TOS
TOS
Figure 6- 128. Routers Links Advertisements
Description
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).
When set, the router is an Autonomous System (AS) boundary
router (E is for External).
When set, the router is an area border router (B is for Border).
The number of router links described by this advertisement. This
must be the total collection of router links to the area.
Options
Link-State ID
Advertising Router
Link-State Sequence Number
Length
Number of Links
Link ID
Link Data
TOS 0 Metric
0 Metric
...
0 Metric
...
Link ID
Link Data
148
Link-State Type