ThediffservapproachtoprovidingQoSinnetworksemploysasmall,well-definedsetofbuildingblocksfromwhichyoucanbuildavarietyof().Itsaimistodefinethedifferentiatedservices(DS)byte,theTypeofService(ToS)bytefromtheInternetProtocolVersion4(________)andtheTrafficClassbytefromIPVersion6,andmarkthestandardizedDSbyteofthepacketsuchthatitreceivesaparticularforwardingtreatment,orper-hopbehavior(PH B),ateachnetworknode.Thediffservarchitectureprovidesa()withinwhichserviceproviderscanoffercustomersarangeofnetworkservices,eachdifferentiatedbasedonperformance.Acustomercanchoosethe()levelneededonapacket-by-packetbasisbysimplymarkingthepacket'sDifferentiatedServicesCodePoint(DSCP)fieldtoaspecificvalue.This()specifiesthePHBgiventothepacketwithintheserviceprovidernetwork。横线处应选() (72)Amessage B.Packet C.header D.package
A.message
B.Packet
C.header
D.package
正确答案是C