Technical information

ADC Telecommunications, Inc.
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HAPTER 12: CONFIGURING IP ROUTING
Defining OSPF Areas
You can divide an autonomous system into smaller, more manageable
sub-divisions called areas. This serves to reduce the size of each routers
routing database. It reduces the amount of routing information that must
travel through the network.
The Cuda 12000 supports two OSPF Area parameters configuration
functions:
Defining stub areas
Assigning specific costs to the default summary route.
To define OSPF Area parameters, follow this procedure:
1. In the OSPF Global window, click the OSPF Areas tab.
2. Click the Summary tab. The Summary window appears.
Import No External. Configures the router to ignore routes
contained in external link state advertisements.
SPF Runs The number of times that the intra-area route table has been
calculated using this area's link-state database. This is
typically done using Dijkstra's algorithm.
ABR Count The total number of area border routers reach- able within
this area. This is initially zero, and is calculated in each SPF
Pass.
ASBR Count The total number of Autonomous System border routers
reachable within this area. This is initially zero, and is
calculated in each SPF Pass
LSA Cksum
The 32-bit unsigned sum of the LS checksums for link-state
advertisements, that are contained in this area's link-state
database. This sum excludes external (LS type 5) link-state
advertisements. The sum can be used to determine if there
has been a change in a router's link state data- base, and to
compare the link-state database of two routers.
Summary
Shows whether summary link state advertisements are to be
sent.
Area Status Shows whether this area is currently Active or Inactive.
Parameter Description