选择题在一台Cisco路由器上执行show access-lists命令显示如下一组信息Extended IP access list port4444
permit icmp 202.38.97.0, wildcard bits 0.0.0.255 any
deny icmp any any
deny udp any any eq 1434
deny tcp any any eq 4444
permit ip any any
根据上述信息，正确的access-list配置是______。

A、 Router(config)#ip access-list extended port4444 Router(config-ext-nacl)#deny icmp any any 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 icmp 202.38.97.0 0.0.0.255 any Router(config-ext-nacl)#permit ip any any
B、 Router(config)#access-list port4444 permit icmp 202.38.97.0 0.0.0.255 any Router(config)#access-list port4444 deny icmp any any Router(config)#access-list port4444 deny udp any any eq 1434 Router(config)#access-list pon4444 deny tcp any any eq 4444 Router(config)#access-list port4444 permit ip any any
C、 Router(config)#ip access-list extended pon4444 Router(config-ext-nac])#permit 202.38.97.0 0.0.0.255 any icmp Router(config-ext-nacl)#deny any any icmp Router(config-ext-nacl)#deny any any udp eq 1434 Router(config—ext-nac])#deny any any tcp eq 4444 Router(config-ext-nacl)#permit ip any any
D、 Router(config)#ip access-list extended port4444 Router(config-ext-nacl)#permit icmp 202.38.97.0 0.0.0.255 any Router(config-ext-nacl)#deny icmp any any Router(config-ext-nacl)#deny udp any any eq 1434 Router(config-ext-nac])#deny tcp any any eq 4444 Router(config-ext-nacl)#permit ip any any

【正确答案】 D

【答案解析】从Extended IP access list port444可以看出，访问列表采用了扩展配置模式，且访问列表名称为port4444。命令为：ip access-list extended port4444。从permit icmp 202.38.97.0, wildcard bits 0.0.0.255 any可以看出，封禁ICMP协议，只允许202.38.97.0/24子网的ICMP报通过路由器。此外，其他的ICMP报全部禁止通过。命令为：permit icmp 202.38.97.0 0.0.0.255 any；deny icmp any any。从deny udp any any eq 1434；deny tcp any any eq 4444；permit ip any any可以看出，禁止了端口为1434的UDP数据包和端口为4444的TCP数据包。命令为：deny udp any any eq 1434；deny tcp any any eq 4444。从permit ip any any司以看出，允许所有IP数据包通过路由器。命令为：permit ip any any，故选择D选项。