NA104.4 110题目求解

afrous

QUESTION 110
Refer to the exhibit. The following commands are executed on interface fa0/1 of 2950Switch.
2950Switch(config-if)# switchport port-security
2950Switch(config-if)# switchport port-security mac-address sticky
2950Switch(config-if)# switchport port-security maximum 1
The Ethernet frame that is shown arrives on interface fa0/1. What two functions will occur when this frame
is received by 2950Switch? (Choose two.)

A. The MAC address table will now have an additional entry of fa0/1 FFFF.FFFF.FFFF.
B. Only host A will be allowed to transmit frames on fa0/1.
C. This frame will be discarded when it is received by 2950Switch.
D. All frames arriving on 2950Switch with a destination of 0000.00aa.aaaa will be forwarded out fa0/1.
E. Hosts B and C may forward frames out fa0/1 but frames arriving from other switches will not be
forwarded out fa0/1.
F. Only frames from source 0000.00bb.bbbb, the first learned MAC address of 2950Switch, will be
forwarded out fa0/1.

Answer: BD
Explanation/Reference:
考点：考查交换机端口安全。maximum 1说明只允许一个mac通过。
A：添加ffff.ffff.ffff到mac地址表，错误。这是个arp报文，把数据包源mac添加到mac表
B：仅允许主机A通过f0/1，正确
C:当2950switch收到帧后丢弃，错误。应该是除f0/1外所有端口洪泛
D：当2950switch收到目的为0000.00aa.aaaa的数据帧会从f0/1转发，正确。
E：主机B和C的数据帧会从f0/1转发，但从其他交换接收到的不会，错误。
F：仅有源mac为0000.00bb.bbbb，2950switch第一个学习到的mac地址才有从f0/1转发。错误。

下面的解释仅仅是这几个选项的翻译，能不能分别说明一下为什么其他选项都错在什么地方。

xiaoqiu

弱弱的问一句，那个主页上的CCNA最新V104.4题库包括了所有的题库吗，同时有非实验题和实验题吗

afrous

xiaoqiu 发表于 2011-7-10 14:53

                               
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弱弱的问一句，那个主页上的CCNA最新V104.4题库包括了所有的题库吗，同时有非实验题和实验题吗

恩 里面都有，应该是全的了……

小乔

E 只有目的mac是0000.00aa.aaaa的才会转发给F0/1
F从f0/1转发的只考虑帧的目的地址，别的都是浮云
  

afrous

小乔 发表于 2011-7-10 18:53

                               
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E 只有目的mac是0000.00aa.aaaa的才会转发给F0/1
F从f0/1转发的只考虑帧的目的地址，别的都是浮云

谢谢小乔……