Withoutproper safeguards,everypartofanetworkisvulnerabletoasecuritybreachor unauthorizedactivityfrom(),competitors,orevenemployees.Manyof theorganizationsthatmanagetheirown (本题)networksecurityanduse theInternetformorethanjustsending/receivinge-mailsexperiencea network()—andmorethanhalfofthesecompaniesdo notevenknowtheywereattacked.Smaller ()areoftencomplacent, havinggainedafalsesenseofsecurity.Theyusuallyreacttothelastvirus orthemostrecentdefacingoftheirwebsite.Buttheyare trappedina situationwheretheydonothavethenecessarytimeand() tospendonsecurity.
A.exterior B.internal C.centre D.middle正确答案B
