* Refer to the exhibit. When Router D is configured to use a link-state routing protocol and is added to the network, what is the first thing that it does to begin learning the network topology?
It learns about its directly connected networks when its interfaces reach the up state.
* What two events will cause a link state router to send LSPs to all neighbors? (Choose two.)
Whenever the network topology changes
Upon initial startup of router or routing protocol
* What is the final step in the link state routing process?
SPF computes best path to each destination network
* What two statements correctly describe the link state routing process? (Choose two.)
Each router in the area floods LSPs to all neighbors
All routers in the area have identical link state databases
* Refer to the exhibit. What kind of information would be seen in an LSP sent from router JAX to router ATL?
Cost of the link
* What feature do modern link-state protocols provide to minimize processing and memory requirements?
Splitting routing topologies into smaller areas
* To achieve network convergence, what three steps does each link state router take? (Choose three.)
Build a Link State Packet (LSP) containing the state of each directly connected link
Flood the LSP to all neighbors, who then store all LSPs received in a database
Construct a complete map of the topology and compute the best path to each destination network
* What speeds up convergence in a network using link-state routing?
Updates triggered by network changes
* Why is it difficult for routing loops to occur in networks that use link-state routing?
Each router builds a complete and synchronized view of the network.
* What are some of the advantages of using a link-state routing protocol instead of a distance vector routing protocol? (Choose two.)
Routers have direct knowledge of all links in the network and how they are connected.
After the inital LSA flooding, they generally require less bandwidth to communicate
Changes in a topology.
* Which algorithm is run by link-state routing protocols to calculate the shortest path to destination networks?
Dijkstra
* Refer to the exhibit. Which statement correctly describes the path traffic would take from the 10.0.0.0/24 network to the 192.168.1.0/24 network if a link-state routing protocol was in use?
BOS -> ORL -> JAX -> ATL because this path is the lowest cost
* Which database or table must be identical on all link-state routers within an area in order to construct an accurate SPF tree?
Link-state database
* Which two routing protocols use Dijkstra’s shortest path first algorithm? (Choose two.)
IS-IS
OSPF
* When are link-state packets sent to neighbors?
When a link goes up or down
* Refer to the exhibit. What does JAX do with link-state packets from ORL?
Sends out the individual link-state packets out the interface connected to BOS
* A new network administrator is given the task of selecting an appropriate dynamic routing protocol for a software development company. The company has over 100 routers, uses CIDR and VLSM, requires fast convergence, and uses both Cisco and non-Cisco equipment. Which routing protocol is appropriate for this company?
OSPF
* What action does a link-state router take immediately upon receipt of an LSP from a neighboring router?
Floods the LSP to neighbors
* Refer to the exhibit. If all routers and interfaces are configured to use a link-state routing protocol, from which routers will router D receive hello packets?
B and C
CCNA 2 V.4 Exploration - Chapter 11
* Refer to the exhibit. What does the "O*E2" from the "O*E2 0.0.0.0/0 [110/1] via 192.168.1.1, 00:05:34, Serial0/0" line represent?
An external OSPF route that will not increment in cost
* Refer to the exhibit. What is the cost of the route to the 10.0.0.0 network?
1786
* What three parameters must be indentical between OSPF routers in order to form an adjacency? (Choose three.)
Area id Hello interval Network type
* What does OSPF use to reduce the number of exchanges of routing information in networks where large numbers of neighbors are present? (Choose two.)
Designated router Backup designated router
* What does OSPF use to calculate the cost to a destination network?
Bandwidth
* A fully converged five router OSPF network has been running successfully for several weeks. All configurations have been saved and no static routes are used. If one router looses power and reboots, what information will be in its routing table after the configuration file is loaded but before OSPF has converged?
Routes for connected networks that are operational will be in the routing table.
* Refer to the exhibit. Router A is correctly configured for OSPF. Which OSPF configuration statement or set of statements was entered for router B to generate the exhibited routing table?
B(config-router)# network 192.168.1.0 0.0.0.3 area 0
* Refer to the exhibit. Which network command or set of sommands will cause OSPF to be enabled to send and receive packets for any R1 interface in the exhibited subnets?
R1(config-router)# network 0.0.0.0 255.255.255.255 area 0
* Refer to the exhibit. What does the "2" stand for in the router ospf 2 statements?
The number 2 identifies this particular instance of OSPF on this router.
* Refer to the exhibit. All routers have been configured with the interface priorities that are shown. All routers were restarted simultaneously. The results of the DR/BDR election are shown. What can be concluded about this network?
The highest router ID was most likely determined via an OSPF router-id statement or statements.
* Refer to the exhibit. What configuration statements would give the results that are shown in the output of the show ip protocols command
* Refer to the exhibit. How many OSPF adjacencies must be formed to build the complete topology if a DR or BDR were not elected in this OSPF network?
6
* What is the default administrative distance for OSPF?
110
* Refer to the exhibit. Routers A, B, C, and D are all running OSPF with default router IDs and OSPF interface priorities. Loopback interfaces are not configured and all interfaces are operational. Router D is the DR and router C is the BDR. What happens immediately after the following commands are entered on router A?
A(config)# interface fa0/0 A(config-if)# ip ospf priority 255 D will remain the DR. C will remain the BDR.
* Refer to the exhibit. All routers are running OSPF. What cost would JAX put in its routing table for the 10.0.0.0/24 network?
1787
* What range of networks will be advertised in the OSPF updates by the command Router1(config-router)# network 192.168.0.0 0.0.15.255 area 100?
192.168.0.0/24 through 192.168.15.0/24
* Refer to the exhibit. The network administrator wants to set the router ID of Router1 to 192.168.100.1. What steps must the administrator take to accomplish this?
Nothing, the router-id of Router1 is already 192.168.100.1
* Refer to the exhibit. When OSPF is operational in the exhibited network, what neighbor relationship is developed between Router1 and Router2?
A FULL adjacency is formed.
* Refer to the exhibit. Assuming that the routers have default interface OSPF priorities and no configured loopback interfaces, what two roles will router B play on each network segment? (Choose two.)
DR for network 192.168.1.200 BDR for network 192.168.1.204
* Refer to the exhibit. Router1 and Router2 are running OSPF. The show ip ospf neighbor command reveals no neighbors. What is a possible cause?
OSPF hello or dead timers do not match.
* Refer to the exhibit. Which command sequence on RouterB will redistribute a gateway of last resort to the other routers in OSPF area 0?
RouterB(config)# ip route 0.0.0.0 0.0.0.0 172.16.6.6 RouterB(config)# ip route 0.0.0.0 0.0.0.0 172.16.6.6 RouterB(config)# router ospf 10 RouterB(config-router)# default-information originate
* Refer to the exhibit. RouterA, RouterB, and RouterC in the diagram are running OSPF on their Ethernet interfaces. Router D was just added to the network. Routers are configured with the loopback interfaces (Lo 0) that are shown in the exhibit. What happens to the OSPF DR/BDR after RouterD is added to the network?
There is no change in the DR or BDR until either current DR or BDR goes down.
* Which two statements describe the use of OSPF DR/BDR elections? (Choose two.)
Elections are required in broadcast multiaccess networks. Elections are required in non-broadcast multiaccess networks.
* Refer to the exhibit. The routers in the exhibit are using default OSPF configuration settings to advertise all attached networks. If all of the routers start at the same time, what will be the result of the DR and BDR elections for this single area OSPF network? (Choose three.)
Router A will be DR for 10.4.0.0/16. HQ will be BDR for 10.4.0.0/16. Remote will be DR for 10.5.0.0/16.
* Refer to the exhibit. What must be received between neighbors to prevent the dead time that is shown in the exhibit from reaching zero?
