Two BGP peers connected through a routed firewall are unable to establish a peering relationship. What could be the most likely cause？（）

单项选择题AnetworkiscomposedofseveralVRFs.ItisrequiredthatVRFusersVRF_AandVRF_BbeabletoroutetoandfromVRF_C，whichhostssharedservices.However，trafficmustnotbeallowedtoflowbetweenVRF_AandVRF_B.Howcanthisbeaccomplished？（）

A.route redistribution
B.import and export using route descriptors
C.import and export using route targets
D.Cisco MPLS Traffic Engineering

单项选择题WhichofthesetablesisusedbyanLSRtoperformaforwardinglookupforapacketdestinedto anaddresswithinanRFC4364VPN？（）

A.CEF
B.FIB
C.LFIB
D.IGP

单项选择题panningTreeProtocolcalculatespathcostbasedonwhichofthese？（）

A.interface bandwidth
B.interface delay
C.interface bandwidth and delay
D.hop count
E.bridge priority

单项选择题Anexpandingcompanyisdeployingleasedlinesbetweenitsmainsiteandtworemotesites.Thebandwidthoftheleasedlinesis128kb seach，terminatedondifferentserialinterfacesonthemainrouter.TheselinksareusedforcombinedVOIPanddatatraffic.ThenetworkadministratorhasimplementedaVOIPsolutiontoreducecosts，andhasthereforereservedsufficientbandwidthinalowlatencyqueueoneachinterfacefortheVOIPtraffic.Usersnowcomplainaboutbadvoicequalityalthoughnodropsareobservedinthelowlatencyqueue.Whatactionwilllikelyfixthisproblem？（）

A.mark VOIP traffic with IP precedence 6 and configure only ’fair-queue’ on the links
B.configure the scheduler allocate 3000 1000 command to allow the QoS code to have enough CPU cycles
C.enable class-based traffic shaping on the VoIP traffic class
D.enable Layer 2 fragmentation and interleaving on the links
E.enable Frame Relay on the links and send voice and data on different Frame Relay PVCs

多项选择题WhichtwooftheseareusedintheselectionofarootbridgeinanetworkutilizingSpanningTreeProtocolIEEE802.1D？（）

A.Designated Root Cost
B.bridge ID priority
C.max age
D.bridge ID MAC address
E.Designated Root Priority
F.forward delay