在下列内容中，属于被动控制措施的是()。

is verification, you notice that the OSPF route of 172.16.10.0 is repeatedly appearing and disappearing from the routing table. Further investigation finds that the OSPF CPU utilization is very high and the routers are constantly performing SPF calculations. You determine that 172.16.20.2 is the source of the 172.16.10.0 route. Using the show ip ospf database router 172.16.20.1 command, you notice that when this show command is performed repeatedly, the contents of the LSA change every few seconds.What could be the cause of this problem？（）

A. OSPF authentication errors between some of the routers

B. Two routers have the same OSPF router ID

C. Issues with mistuned OSPF timers

D. OSPF LSA pacing issues between some of the routers

E. OSPF neighbor adjacency problems between some of the routers

A．A

B．B

C．C

D．D

A．32

B．128

C．256

D．1000

A. area IDs

B. process IDs

C. router IDs

D. hello timers

t？As a Network Engineer, it is necessary for you to know how to implement MPLS VPNs between Customer Edge and Provider Edge routers.Refer to the following descriptions, which one is making sense？（）

A. If using OSPF or EIGRP as the PE-CE routing protocol, redistribution is not required, but any other protocol or static route will require redistribution

B. If using IS-IS as the PE-CE routing protocol, no redistribution is required

C. If using static routes between the CE and PE routers, no redistribution of other VPN routes is required

D. If PE-CE protocol is not BGP, redistribution of other VPN routes from MP-BGP is required

A．A

B．B

C．C

D．D

E．E

A．A

B．B

C．C

D．D

uters are not becoming EIGRP neighbors. A ping between the two routers was successful.What is the next thing that should be checked？（）

A. Verify that the EIGRP hello and hold timers match exactly.

B. Verify that EIGRP broadcast packets are not being dropped between the two routers with the show ip EIGRP peer command.

C. Verify that EIGRP broadcast packets are not being dropped between the two routers with the show ip EIGRP traffic command.

D. Verify that EIGRP is enabled for the appropriate networks on the local and neighboring router.

been tasked to implement a hub and spoke EIGRP topology over Frame Relay to provide connectivity between the networks at headquarters and all 300 spokes. Before you begin the actual implementation, which three pieces of information are more important to know than the others？（）

A. the Committed Information Rate of all the Frame Relay PVCs

B. the Cisco IOS version running on all the routers

C. the router model number of all the spoke routers

D. the number of HQ networks connected behind the headquarter routers

E. the routing policy, such as whether or not the spokes can be used as backup transient point between the two headquarter routers