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The database description packet – D-Link DES-3326S User Manual

Page 146

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

146

Switch Management and Operating Concepts

The Database Description Packet

Database Description packets are OSPF packet type 2. These
packets are exchanged when an adjacency is being initialized.
They describe the contents of the topological database.

Multiple packets may be used to describe the database. For
this purpose a poll-response procedure is used. One of the
routers is designated to be master, the other a slave. The
master seconds Database Description packets (polls) which are
acknowledged by Database Description packets sent by the
slave (responses). The responses are linked to the polls via the
packets’ DD sequence numbers.

Database Description Packet

Version No.

2

P

Router ID

Area ID

Au

Authentication

Authentication

Checksum

DD Sequence No.

Reserved

Reserved

Link-State Advertisement Heade

I M MS

acket Length

thentication Type

Options

r ...

Figure 5-24. Database Description Packet

Field Description

Options The

optional

capabilities

supported by the router.