多项选择题
A.MD5
B.DES
C.Kerberos
D.Unauthenticated
E.Simple password
多项选择题 WhichfourcomponentsmakeuptheNetworkEntityTitle（NET）ofanIS-ISrouter？（）
单项选择题 RoutersAandBareconnectedwithapoint-to-pointOC-3interface.Eachrouter’sOC-3interfaceisconfiguredforbothLevel1andLevel2.Theroutersareconfiguredindifferentareas.HowmanyIS-ISadjacenciesexistbetweenthetworouters？（）
单项选择题 InIS-IS，howdoestherestartingrouterinformitshelpersthatarestartseventoccurred？（）