What is one of the reasons that custom QoS ACLs are recommended over automatic QoS when configuring ports on a Catalyst 6500 for use with IP phones？（）

单项选择题VLANTagging，alsoknownasFrameTagging，isamethoddevelopedbyCiscotohelpidentify packetstravellingthroughtrunklinks.WhenanEthernetframetraversesatrunklink，aspecial VLANtagisaddedtotheframeandsentacrossthetrunklink.HowdoesERSusetheVLANtag？（）

A. provide service internetworking
B. support transparency for Layer 2 frames
C. indicate destination as a connection identifier
D. map to the DLCI in service internetworking

单项选择题WhichofthesestatementsbestdescribesVPLS？（）

A. Neither broadcast nor multicast traffic is ever flooded in VPLS.
B. Multicast traffic is flooded but broadcast traffic is not flooded in VPLS.
C. VPLS emulates an Ethernet switch， with each EMS being analogous to a VLAN.
D. Because U-PE devices act as IEEE 802.1 devices， the VPLS core must use STP.
E. When the provider experiences an outage， IP re-routing restores PW connectivity and MAC re-learning is needed.

多项选择题WhichtwobenefitsdoesVoFRprovide？（）

A. bandwidth efficiency
B. cell-switching
C. congestion notification
D. heterogeneous network

单项选择题AFibreChannelfabric（orFibreChannelswitchedfabric，FC-SW）isaswitchedfabricofFibreChanneldevicesenabledbyaFibreChannelswitch.FabricsarenormallysubdividedbyFibre Channelzoning.Eachfabrichasanameserverandprovidesotherservices.HigherredundancyoverFC-AL，P2P.WhichpathselectionprotocolisusedbyFibreChannelfabrics？（）

A. OSPF
B. RIP
C. FSPF
D. VSANs

单项选择题ThenetworkadministratorwouldliketogeneratesynthetictrafficusingtheServiceAssuranceAgentcontainedinCiscoIOS.WhichCiscoWorksnetworkmanagementapplicationwillbeusedtoreportthelatencyandavailabilityforconfiguredtrafficoperationsonanend-to-endandhop-by-hop（router-to-router）basis？（）

A. nGenius Real-Time Monitor
B. CiscoView
C. Device Fault Manager
D. Internetwork Performance Monitor