Designated Routers In Multi-Access Networks - Dell PowerConnect B-RX Configuration Manual

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Overview of OSPF (Open Shortest Path First)
An Autonomous System Boundary Router (ASBR) is a router that is running multiple protocols and
serves as a gateway to routers outside an area and those operating with different protocols. The
ASBR is able to import and translate different protocol routes into OSPF through a process known
as redistribution. For more details on redistribution and configuration examples, refer to
route redistribution"
FIGURE 101

Designated routers in multi-access networks

In a network that has multiple routers attached, OSPF elects one router to serve as the designated
router (DR) and another router on the segment to act as the backup designated router (BDR). This
arrangement minimizes the amount of repetitive information that is forwarded on the network by
forwarding all messages to the designated router and backup designated routers responsible for
forwarding the updates throughout the network.
676
on page 702.
OSPF operating in a network
Area 0.0.0.0 Backbone
Area 192.5.1.0
Router A
Router C
Area 195.5.0.0
Router D
208.5.1.1
Area Border
Router (ABR)
Virtual Link
e8
206.5.1.1
Router B
Area Border
Router (ABR)
Router G
RIP Router
"Enable
Area 200.5.0.0
Router E
Router F
Autonomous System
Border Router (ASBR)
BigIron RX Series Configuration Guide
53-1001810-01