未知题型

A.OSPFovermulticastEMSorVPLSnetworkmaynothaveconsistentbroadcastormulticastperformance
B.IPmulticastisnotsupportedoverLover3MPLSVPN;insteadaLayer2MPLSWNmustbeutilizedwithserviceprovidersupport
C.QoSrequirementswithMPLS-VPNmustbeimplementedbytheserviceprovider
D.HierarchicalVPLSdesignsaretheleastscalable
E.IGMPsnoopingisnotonoptionwithVPLSorEMS;insteadadministrativescopingorallowingsufficientbandwidthforunnecessarymulticasttrafficattheedgelinksisrequired
【参考答案】

A, C