单项选择题
Which of the following is used to periodically multicast by DIS on a LAN to ensure IS-IS link state databaseaccuracy？（）
A.CSNP B.LSP C.ISH D.Hello E.IIH F.PSNP
单项选择题 MPLSlabelmappingonanLSRisdisplayedbywhichIOScommand？（）
多项选择题 WhichthreeprotocolsuseTLVstocarryattributes？（）
单项选择题 HowmanymessagesdoesinternetKeyExchangeusetonegotiateSAcharacteristicswhenrunninginmainmode？（）
