beautypg.com

D-Link DES-3326 User Manual

Page 75

background image

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

The format of the Hello packet is shown below:

Hello Packet

1

Packet Length

Router ID

Area ID

Version No.

Checksum

Authentication Type

Authentication

Authentication

Network Mask

Hello Interval

Options

Router Priority

Router Dead Interval

Designated Router

Backup Designated Router

Neighbor

Figure 5-26. Hello Packet

Field

Description

Network Mask

The network mask associated with this interface.

Options

The optional capabilities supported by the router.

Hello Interval

The number of seconds between this router’s Hello
packets.

Router Priority

This router’s Router Priority. The Router Priority is
used in the election of the DR and BDR. If this field
is set to 0, the router is ineligible to become the DR
or the BDR.

Router Dead Interval

The number of seconds that must pass before
declaring a silent router as down.

Designated Router

The identity of the DR for this network, in the view of
the advertising router. The DR is identified here by
its IP interface address on the network.

Backup Designated Router The identity of the Backup Designated Router (BDR)

for this network. The BDR is identified here by its IP
interface address on the network. This field is set to
0.0.0.0 if there is no BDR.

Neighbor

The Router Ids of each router from whom valid Hello
packets have been seen within the Router Dead
Interval on the network.

75