单项选择题
A.IPSec VPN
B.SSL VPN
C.port security
D.port security with statically configured MAC addresses
E.private VLANs
多项选择题 Yournetworkissufferingfromregularoutages.Aftertroubleshooting，youlearnthatthetransmitleadofafiberuplinkwasdamaged.Whichtwofeaturescanpreventthesameissuesinthefuture？（）
单项选择题 Whileyouaretroubleshootingnetworkperformanceissues，younoticethataswitchisperiodicallyfloodingallunicasttraffic.FurtherinvestigationrevealsthatperiodicallytheswitchisalsohavingspikesinCPUutilization，causingtheMACaddresstabletobeflushedandrelearned.Whatisthemostlikelycauseofthisissue？（）
单项选择题 ForarouterconnectedtotwoISPsforredundancy，usingIPSLAandstaticrouting，howwouldyouconfigureuRPFontheuplinkinterface？（）