Wehavealreadycoveredthetopicofnetworkaddresses.Thefirst(71)inablock(inclassesA,B,and C)definesthenetworkaddress.InclassesA,B,andC,ifthehostidisallls,theaddressiscalledadirectbroadcastaddress.Itisusedbya.(72)tosendapackettoallhostsinaspecificnetwork.Allhostswillacceptapackethavingthistypeofdestinationaddress.Notethatthisaddresscanbeusedonlyasa(73)addressinanlPpacket.NotealsothatthisspecialaddressalsoreducesthenumberofavailablehostidforeachnetidinclassesA,B,and C. InclassesA,B,andC,anaddresswithallIsforthenetidandhostid(32bits)definesa(74)addressinthecurrentnetwork.AhostthatwantstosendamessagetoeveryotherhostcanusethisaddressasadestinationaddressinanIPpacket.However,arouterwillblockapackethavingthistypeofaddresstoconfinethebroadcastingtothe()network.Notethatthisaddressbelongstoclass E.
A.neighbor B.next C.remote D.local正确答案D
