思科网络学院 CCNA2 ERouting Chapter 10

Sian

Assessment Item:

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?

A and E
B and C
A, B, C, and E
C only
Reset
Scoring Rule for:   correctness of response
2 points for Option 2


Assessment Item:
What action does a link-state router take immediately upon receipt of an LSP from a neighboring router?

floods the LSP to neighbors
calculates the SPF algorithm
runs the Bellman-Ford algorithm
computes the best path to the destination network
Reset
Scoring Rule for:   correctness of response
2 points for Option 1


Assessment Item:
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?

RIP version 2
IGRP
EIGRP
OSPF
BGP
Reset
Scoring Rule for:   correctness of response
2 points for Option 4


Assessment Item:

Refer to the exhibit. What does JAX do with link-state packets from ORL?

sends out its updated routing table to both ORL and BOS routers
sends out the individual link-state packets out the interface connected to BOS
queries BOS to see if it has a better route
only adds it to the local routing table and performs no other actions
Reset
Scoring Rule for:   correctness of response
2 points for Option 2


Assessment Item:
When are link-state packets sent to neighbors?

every 30 seconds
every 180 seconds
after the holddown time expires
when a link goes up or down
when a routing loop occurs
Reset
Scoring Rule for:   correctness of response
2 points for Option 4


Assessment Item:
Which two routing protocols use Dijkstra’s shortest path first algorithm? (Choose two.)

RIPv1
RIPv2
IS-IS
BGP
EIGRP
OSPF
Reset
Scoring Rule for:   correctness of response
Option 3 and Option 6 are correct.


Assessment Item:
Which database or table must be identical on all link-state routers within an area in order to construct an accurate SPF tree?

routing table
adjacency table
link-state database
neighbor table
topology database
Reset
Scoring Rule for:   correctness of response
2 points for Option 3




Assessment Item:

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 -> ATL because this path is the least hops
BOS -> ATL because this path is highest cost
BOS -> ORL -> JAX -> ATL because this path is the lowest cost
traffic would load balance across all links
Reset
Scoring Rule for:   correctness of response
2 points for Option 3


Assessment Item:
Which algorithm is run by link-state routing protocols to calculate the shortest path to destination networks?

DUAL
Dijkstra
Bellman-Ford
Diffie-Hellman
Reset
Scoring Rule for:   correctness of response
2 points for Option 2



Assessment Item:
What are two advantages of using a link-state routing protocol instead of a distance vector routing protocol? (Choose two.)

The topology database eliminates the need for a routing table.
Each router independently determines the route to each network.
Link-state protocols require less router processor power than distance vector protocols.
After the inital LSP flooding, they generally require less bandwidth to communicate changes in a topology.
Frequent periodic updates are sent to minimize the number of incorrect routes in the topological database.
Reset
Scoring Rule for:   correctness of response
Option 2 and Option 4 are correct.




Assessment Item:
Why is it difficult for routing loops to occur in networks that use link-state routing?

Each router builds a simple view of the network based on hop count.
Routers flood the network with LSAs to discover routing loops.
Each router builds a complete and synchronized view of the network.
Routers use hold-down timers to prevent routing loops.
Reset
Scoring Rule for:   correctness of response
2 points for Option 3


Assessment Item:
What speeds up convergence in a network using link-state routing?

updates triggered by network changes
updates sent at regular intervals
updates sent only to directly connected neighbors
updates that include complete routing tables
Reset
Scoring Rule for:   correctness of response
2 points for Option 1


Assessment Item:
To achieve network convergence, what three steps does each link state router take? (Choose three.)

use automatic summarization to reduce the size of routing tables
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
send hello packages at regular intervals to discover neighbors and establish adjacencies
construct a complete map of the topology and compute the best path to each destination network
use the DUAL FSM to select efficient, loop-free paths, and insert routes into the routing table
Reset
Scoring Rule for:   correctness of response
Option 2, Option 3, and Option 5 are correct

Assessment Item:
What feature do modern link-state protocols provide to minimize processing and memory requirements?

splitting routing topologies into smaller areas
assigning lower process priorities to route calculations
using update timers to restrict routing updates
strict split horizon rules to reduce routing table entries
Reset
Scoring Rule for:   correctness of response
2 points for Option 1



Assessment Item:

Refer to the exhibit. What kind of information would be seen in an LSP sent from router JAX to router ATL?

hop count
uptime of the route
cost of the link
a list of all the routing protocols in use
Reset
Scoring Rule for:   correctness of response
2 points for Option 3



Assessment Item:
What two statements correctly describe the link state routing process? (Choose two.)

all routers in the area have link state databases
each router in the area floods LSPs to all neighbors
LSPs use the reserved multicast address of 224.0.0.10 to reach neighbors
routing loops are prevented by running the Diffusing Update Algorithm (DUAL)
Reliable Transport Protocol (RTP) is the protocol used by for the delivery and reception of LSPs
Reset
Scoring Rule for:   correctness of response
Option 1 and Option 2 are correct.




Assessment Item:
What is the final step in the link state routing process?

successors are placed into the routing table
SPF computes best path to each destination network
LSPs are flooded to all neighbors to converge the network
DUAL algorithm is run to find best path to destination networks
Reset
Scoring Rule for:   correctness of response
2 points for Option 2



Assessment Item:
What two events will cause a link state router to send LSPs to all neighbors? (Choose two.)

30 second timer expires
whenever the network topology changes
immediately after the Bellman-Ford algorithm has run
immediately after the DUAL FSM has built the topology database
upon initial startup of router or routing protocol
Reset
Scoring Rule for:   correctness of response
Option 2 and Option 5 are correct.




Assessment Item:

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 sends LSP packets to Routers B and C.
It sends LSP packets to all routers in the network.
It sends Hello packets to all routers in the network.
It sends information about its directly connected neighbors to Routers A and E.
It sends information about its directly connected neighbors to all routers in the network.
It learns about its directly connected networks when its interfaces reach the up state.
Reset
Scoring Rule for:   correctness of response
2 points for Option 6