单项选择题
When gateways are registering with a gatekeeper， the gatekeeper can be（）.
A.On the same subnet B.On a remote LAN C.In a different subnet D.Any of the above
单项选择题 WhatistherelationshipbetweentheDomainNameSystem（DNS）andLDAP？（）
多项选择题 TheOSPFExternalLSAforprefixx.x.x.xexistsintheOSPFdatabase，buttheprefixisnotinstalledintheroutingtable.Whicharepossibleexplanations？（）
单项选择题 WhatstatementaboutTransitASistrue？（）
