ENSA - Module 1 - OSPF Concepts

What is used to facilitate hierarchical routing in OSPF?

• • autosummarization

  
  

• 
  the use of multiple areas

• frequent SPF calculations

• 
  the election of designated routers

What is a benefit of multiarea OSPF routing?

• 
  Topology changes in one area do not cause SPF recalculations in other areas.

• 
  Automatic route summarization occurs by default between areas.

• Routers in all areas share the same link-state database and have a complete picture of the entire network.

• A backbone area is not required.

Which OSPF data structure is identical on all OSPF routers that share the same area?

• 
  adjacency database

• 
  link-state database

• 
  routing table

• 
  forwarding database

Which step does an OSPF-enabled router take immediately after establishing an adjacency with another router?

• 
  chooses the best path

• 
  builds the topology table

• executes the SPF algorithm

• 
  exchanges link-state advertisements

A network engineer has manually configured the hello interval to 15 seconds on an interface of a router that is running OSPFv2. By default, how will the dead interval on the interface be affected?

• 
  The dead interval will now be 15 seconds.

• 
  The dead interval will now be 30 seconds.

• The dead interval will now be 60 seconds.

• The dead interval will not change from the default value.

Refer to the exhibit. A network administrator has configured the OSPF timers to the values that are shown in the graphic. What is the result of having those manually configured timers?

• The R1 dead timer expires between hello packets from R2.

• 
  R1 automatically adjusts its own timers to match the R2 timers.

• 
  The hello timer on R2 expires every ten seconds.

• 
  The neighbor adjacency has formed.

Match the following

• advertise new information

• hello packet

• establish and maintain adjacencies

• link-state request packet

• query another route

• Link-state update packet

• compare local topology

• database description packet

To establish a neighbor adjacency two OSPF routers will exchange hello packets. Which two values in the hello packets must match on both routers? (Choose two.)

• 
  router ID

• hello interval

• dead interval

• 
  router priority

• 
  list of neighbors

What is the default router priority value for all Cisco OSPF routers?

• 0

• 1

• 10

• 255

Which type of OSPFv2 packet contains an abbreviated list of the LSDB of a sending router and is used by receiving routers to check against the local LSDB?

• 
  link-state update

• link-state request

• 
  database description

• link-state acknowledgmen