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()
A.information
B.Structure
C.means
D.framework
正确答案是D