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Network links advertisements – D-Link DES-3326 User Manual

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DES-3326 Layer 3 Fast Ethernet Switch User’s Guide

Field

Description

TOS

IP Type of Service that this
metric refers to.

Metric

The cost of using this
outbound router link, for
traffic of the specified TOS.

Table 5-19. Routers Links Advertisement

Continued

Network Links Advertisements

Network links advertisements are Type 2 link state advertisements. A network links advertisement is
originated for each transit network in the area. A transit network is a multi-access network that has
more than one attached router. The network links advertisement is originated by the network’s
Designated router. The advertisement describes all routers attached to the network, including the
Designated Router itself. The advertisement’s Link State ID field lists the IP interface address of the
Designated Router.

The distance form the network to all attached routers is zero, for all TOS. This is why the TOS and
metric fields need not be specified in the network links advertisement.

The format of the Network Links Advertisement is shown below:

Link-State Age

Options

Link-State ID

Advertising Router

Link-State Sequence Number

Link-State Checksum

Length

Network Link Advertisements

2

Network Mask

Attached Router

Figure 5-34. Network Link Advertisement

Field

Description

Network Mask

The IP address mask for the network.

Attached Router

The Router Ids of each of the routers attached to the
network. Only those routers that are fully adjacent
to the Designated Router (DR) are listed. The DR
includes itself in this list.

Table 5-20. Network Link Advertisement

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