在一台Cisco路由器上用show access-list命令得到下列信息 Extended IP access list fengjin1434 deny udp any any eq 1434 deny tcp any any eq 4444 perm

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问题 在一台Cisco路由器上用show access-list命令得到下列信息
Extended IP access list fengjin1434
deny udp any any eq 1434
deny tcp any any eq 4444
permit ip any any
根据以上信息,下列路由器的access-list配置,正确的是(          )。

选项 A、Router(config)#ip access-list standard fengjin1434
Router(config-std-nacl)#deny udp any any eq 1434
Router(config-std-nacl)#deny tep any any eq 4444
Router(config-std-nacl)#permit ip any any
Router(config-std-nacl)#exit
Router(config)#interface g0/1
Router(config-if)#ip access-group fengjin1434 in
Router(config-if)#ip access-group fengjin1434 out
Router(config-if)#
B、Router(config)#interface g0/1
Router(config-if)#ip access-group fengjin1434 in
Router(config-if)#ip access-group fengjin1434 out
Router(config)#ip access-list standard fengjin1434
Router(config-ext-nacl)#deny udp any any eq 1434
Router(config-ext-nacl)#deny tcp any any eq 4444
Router(config-ext-nacl)#permit ip any any
Router(config-ext-nacl)#exit
Router(config-if)#
C、Router(config)#ip access-list extended fengjin1434
Router(config-ext-nacl)#deny udp any any eq 1434
Router(config-ext-nacl)#deny tcp any any eq 4444
Router(config-ext-nacl)#permit ip any any
Router(config-ext-nacl)#exit
Router(config)#interface g0/1
Router(eonfig—if)#ip access—group fengjinl434 in
Router(config-if)#ip access-group fengjin1434 out
Router(config-if)#
D、Router(config)#ip access-list extended fengjin1434
Router(config-ext-nacl)#permit ip any any
Router(config-ext-nacl)#deny udp any any eq 1434
Router(eonfig-ext-nacl)#deny tcp any any eq 4444
Router(config-ext-nacl)#exit
Router(config)#interface g0/1
Router(config-if)#ip access-group fengjin1434 in
Router(config-if)#ip access-group fengjin1434 out
Router(config-if)#

答案C

解析 A、B选项采用标准的访问控制列表(standard),可以排除;排除某个协议或者端口时,配置语句应该先拒绝排除的协议或者端口,然后允许其它协议或者端口进行数据传输,D选项是先允许后拒绝,D选项错误。故选择C选项。
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