默认题库 - CCNA(640-802)

单选题

Three switches are connected to one anther via trunk ports.Assuming the default switch configuration,which switch is elected as the root bridge for the spanning-tree instance of vlan 1?（）

A. the switch with the lowest MAC address
B. the switch with the higest MAC address
C. the switch witch the higest IP address
D. the switch with the lowest IP addre

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单选题

Which command displays the CHAP authentication process as it occurs between two routers?（）

A. debug authentication
B. debug chap ppp
C. debug chap authentication
D. debug ppp authenticatio

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单选题

Which statement describes the rule of split horizon?（）

A. Only router can split boundaries(horizons)between concentric networks.
B. All distance vector protocols require fall routes that may cause momentary loops as the topology changes.
C. Networks can only remain fully converged if all information about routes is sent out all active interfaces.
D. Information about a route should not be sent back in the direction from which the original update came.
Each AS must keep routing tables converged to prevent dead routes from being advertised across the AS boundary.

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单选题

After the show ip route command has been entered,the follwing routes are displayed.Which route will not be entered into the routing table of a neighboring router?（）

A. R 192.168.8.0/24 [120/1] via 192.168.2.2, 00:00:10, Serial0
B. R 192.168.11.0/24 [120/7] via 192.168.9.1, 00:00:03, Serial1
C 192.168.1.0/24 is directly connected, Ethernet 0
D. R 192.168.5.0/24 [120/15] via 192.168.2.2,00:00:10,Serial0

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多选题

Host 1 is trying to communicate with Host 2. The e0 interface on Router C is down. Which of the following are true?（）

A. Router C will use ICMP to inform Host 1 that Host 2 cannot be reached.
B. Router C will use ICMP to inform Router B that Host 2 cannot be reached.
C. Router C will use ICMP to inform Host 1, Router A, and Router B that Host 2 cannot be reached.
D. Router C will send a Destination Unreachable message type.
E. Router C will send a Router Selection message type.
F. Router C will send a Source Quench message type.

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多选题

Which two devices can interfere with the operation of a wireless network because they operate on similar frequencies?（）

A. copier
B. microwave oven
C. toaster
D. cordless phone
E. IP phone
F. AM radio

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单选题

Assuming default setting,how can you erase the VTP database of VLANs on a CISCO IOS switch running in VTP server mode?（）

A. Enable VTP pruning
B. From privileged mode ,erase the startup configuration file,then reload.
C. From privileged mode ,erase the vlan date file, then reload.
D. Cycle the switch power.

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多选题

What are two reasons that a network administrator would use access lists? (Choose two.) （）。

A. to control vty access into a router
B. to control broadcast traffic through a router
C. to filter traffic as it passes through a router
D. to filter traffic that originates from the router
E. to replace passwords as a line of defense against security incursions&e

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多选题

Two switches are connected through a trunk link.which two commands show that there is a native VLAN mismatch on that link?（）

A. show interfaces interface
B. show vlan bri
C. show interfaces interface switchport
D. show interface interface trunk
E. show interfaces vla

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多选题

To configure the VLAN trunking protocol to communicate VLAN information between two switches, what two requirements must be met?（）

A. Each end of the trunk line must be set to IEEE 802.1E encapsulation.
B. The VTP management domain name of both switches must be set the same.
C. All ports on both the switches must be set as access ports.
D. One of the two switches must be configured as a VTP server.
E. A rollover cable is required to connect the two switches together.
F. A router must be used to forward VTP traffic between VLANs.

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