D-Link DES-3326SR, Руководство пользователя

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D-Link DES-3326SR Layer 3 Switch
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
Table 6. 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 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.
Field Description
Neighbor The Router Ids of each router from whom valid Hello packets
have been seen within the Router Dead Interval on the network.
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.
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