ccnp最新题库

魏茂义

1.Based on this FIB table, which statement is correct?

A. There is no default gateway.

B. The IP address of the router on FastEthernet is 209.168.201.1.

C. The gateway of last resort is 192.168.201.1.

D. The router will listen for all multicast traffic.

Answer: C

Explanation:

The 0.0.0.0/0 route is the default route and is listed as the first CEF entry. Here we see the next hop for

this default route lists 192.168.201.1 as the default router (gateway of last resort).

2. A network administrator checks this adjacency table on a router. What is a possible cause for the

incomplete marking?

A. incomplete ARP information

B. incorrect ACL

C. dynamic routing protocol failure

D. serial link congestion

Answer: A

3.A network engineer notices that transmission rates of senders of TCP traffic sharply increase and

decrease simultaneously during periods of congestion. Which condition causes this?

A. global synchronization

B. tail drop

C. random early detection

D. queue management algorithm

Answer:  A

4.Which three problems result from application mixing of UDP and TCP streams within a network with no

QoS? (Choose three.)

A. starvation

B. jitter

C. latency

D. windowing

E. lower throughput

Answer:  A,C,E

Explanation:

It is a general best practice not to mix TCP-based traffic with UDP-based traffic (especially streaming

video) within a single service provider class due to the behaviors of these protocols during periods of

congestion. Specifically, TCP transmitters will throttle-back flows when drops have been detected.

Although some UDP applications have application-level windowing, flow control, and retransmission

capabilities, most UDP transmitters are completely oblivious to drops and thus never lower transmission

rates due to dropping. When TCP flows are combined with UDP flows in a single service provider class

and the class experiences congestion, then TCPflows will continually lower their rates, potentially giving

up their bandwidth to drop-oblivious UDP flows. This effect is calledTCP-starvation/UDP-dominance.This

can increase latency and lower the overall throughput. TCP-starvation/UDP-dominance likely occurs if

(TCP-based) mission-critical data is assigned to the same service provider class as (UDP-based)

streaming video and the class experiences sustained congestion. Even if WRED is enabled on the

service provider class, the same behavior would be observed, as WRED (for the most part) only affects

TCP-based flows. Granted, it is not always possible to separate TCP-based flows from UDP-based flows,

but it is beneficial to be aware of this behavior when making such application-mixing decisions.

6.Which statement about the use of tunneling to migrate to IPv6 is true?

A. Tunneling is less secure than dual stack or translation.

B. Tunneling is more difficult to configure than dual stack or translation.

C. Tunneling does not enable users of the new protocol to communicate with users of the old protocol

without dual-stack hosts.

D. Tunneling destinations are manually determined by the IPv4 address in the low-order 32 bits of

IPv4-compatible IPv6 addresses.

Answer:  C

Explanation:

Using the tunneling option, organizations build an overlay network that tunnels one protocol over the other

by encapsulating IPv6 packets within IPv4 packets and IPv4 packets within IPv6 packets. The advantage

of this approach is that the new protocol can work without disturbing the old protocol, thus providing

connectivity between users of the new protocol. Tunneling has two disadvantages, as discussed in RFC

6144:

Users of the new architecture cannot use the services of the underlying infrastructure.

Tunneling does not enable users of the new protocol to communicate with users of the old protocol

without dual-stack hosts, which negates interoperability.

7.A network administrator executes the command clear ip route. Which two tables does this command

clear and rebuild? (Choose two.)

A. IP routing

B. FIB

C. ARP cache

D. MAC address table

E. Cisco Express Forwarding table

F. topology table

Answer:  A,B

免费教学：http://www.wyzc.com/ccna/?tg=YmRzb5=HO

保过认证：http://www.wyzc.com/kecheng/ccnp/?tg=YmRzb5=HO

咨询热线：18501047867    QQ：2850361036    Q群：191762243

  

魏茂义

自己顶一下，希望大家喜欢

zhswy1234

krz520218

start110