一篇文件的主题词是表达文件的主旨、概括文件内容特征的，因此它的词义必须明确清晰，使用的概念必

A.HMAC-MD5

B.HMAC-SHA

C.CBC-DES

D.community strings

A. Create an additional ACL to block the access to VLAN 1.

B. Move the management VLAN to something other than default.

C. Move all ports to another VLAN and deactivate the default VLAN.

D. Limit the access in the switch using port security configuration.

E. Use static VLAN in trunks and access ports to restrict connections.

F. Shutdown all unused ports in the Catalyst switch.

A.SiteOfOriginSOO.

B.SHAMlinkswithOSPF

C.BGPcostcommunity

D.BGPfeatureallow-asin

E.RPFReversePathforwarding.

F.Access-listControlinDistanceVectorprotocollikeRIPandEIGRP.

A.Sniffingattack

B.Denialofserviceattack

C.PortScanattack

D.Reconnaisanceattack

E.Spoofingattack

A.Anupdatepacketwithinitflagsetfromaknown，alreadyestablishedneighborrelationshipwasreceivedbyoneoftherouters.

B.TheARPcachewascleared.

C.Thecounterswerecleared.

D.TheIPEIGRPneighborrelationshipwasclearedmanually.

A.Ifalabeledpacketarriveswiththetopmostlabelof17，itwillbereplacedwithlabel19andsentouton Ethernet0/0interface.

B.Ifalabeledpacketarriveswiththetopmostlabelof19，itwillbereplacedwithlabel17andsentouton Ethernet0/0interface.

C.Ifalabeledpacketarriveswiththetopmostlabelof17，allthelabelswillberemovedandaclearIP PacketissenttoNextHop192.168.0.14onEthernet0/0.

D.Noneoftheabove.

A. 802.1Q native VLAN frames are untagged by default.

B. 802.1Q trunking ports can also be secure ports.

C. 802.1Q trunks can use 10 Mb/s Ethernet interfaces.

D. 802.1Q trunks require full-duplex, point-to-point connectivity.

E. 802.1Q trunks should have native VLANs that are the same at both ends.