A.root guardB.loop guardC.BPDU guardD.UDLDE.BPDU skew d……

单项选择题CustomerXhasahub-and-spokeFrameRelaynetwork，withacentralofficeandtwobranchoffices（RemoteAandRemoteB）.EachlocationhasonlyonephysicallinktotheFrameRelaycloudandRemoteBhasarouterthatisnotaCiscorouter.Sincetheinstallation，thereisnoconnectivitybetweenRemoteBandthecentraloffice.Whatisapossiblesolutiontothisissue？（）

A. Because Frame Relay IETF encapsulation is only configurable at interface level， you must use IETF encapsulation on all routers.
B. This is not a possible scenario. A dedicated Frame Relay link to RemoteB is mandatory at the central office.
C. The router at RemoteB must be replaced by a Cisco router.
D. Use Frame Relay IETF encapsulation on a per-VC basis on the central office router.
E. There is a problem in the Frame Relay cloud， because Cisco routers are compatible with IETF Frame Relay.

单项选择题ForarouterconnectedtotwoISPsforredundancy，usingIPSLAandstaticrouting，howwouldyouconfigureuRPFontheuplinkinterface？（）

A.ip verify unicast source reachable-via any
B.ip verify unicast reverse-path
C.ip verify unicast reverse-path loose
D.ip verify unicast reverse-path strict

单项选择题Beforeinsertinganewswitchinthenetwork，thenetworkadministratorchecksthattheVTPdomainnameiscorrect，theVTPmodeissettoserver，andrevisionislowerthantheswitchesinthenetwork.Theadministratorthenconfiguresinterfacesandtrunks，erasesexistingVLANs，andconnectstheswitchtothenetwork.Followingthatprocedure，thereisnoconnectivityinthenetwork.Whatisapossiblecauseofthisproblem？（）

A. Because the configuration revision of the new switches is lower than the rest of the network，it can change the VLAN database of the other switches.
B. As a VTP server， the new switch deleted all VLANs of the network.
C. Erasing VLANs increases the VTP configuration revision.
D. Since the configuration revision of the network is higher than the new switch，the VLAN database was automatically synchronized.

多项选择题Refer to the exhibit. Users from the Engineering VLAN complain that every time Business VLAN users have a network connectivity issue， the Engineering VLAN users usually have problems experiencing slow response or network connectivity problems. After troubleshooting， an unauthorized switch 2 was found. This unauthorized switch has been a regular problem， assuming the root bridge function under the spanning-tree domain and causing the  Engineering VLAN to be unstable. Which three of these actions could be suggested to fix the problem？（）

A. Upgrade Spanning Tree Protocol to Rapid Spanning Tree Protocol.
B. Change Business VLAN PCs to switch 1 and switch 4.
C. Force the root bridge to be switch 2， instead.
D. Adjust spanning-tree timers （max-age and forward-delay）.
E. Shut down all unused ports.
F. Use MSTP to separate the Engineering VLAN from the Business VLAN to optimize spanning-tree convergence time within each VLAN

单项选择题WhatistrueaboutIPSourceGuardwithportsecurity？（）

A.Binding should be manually configured.
B.It is not supported if IEEE 802.1x port-based authentication is enabled.
C.The DHCP server must support option 82， or the client is not assigned an IP address.
D.It filters based on source IP address only.