多项选择题
Option 10A （back-to-back VRF） is an implementation of inter-AS MPLS VPN. Which of four statementsabout option 10A are not true？（）
A.MPLS is required between the ASBRs. B.ASBR must hold all routing information. C.It is a scalable solution. D.It is a simple solution. E.MP-EBGP is used to exchange routes between ASBRs.
多项选择题 Whichthreeoftheseareopticalchanneldataunit（ODU）overheadfields？（）
单项选择题 WhichstatementaboutOSPFASBRsummaryLSAistrue？（）
多项选择题 WhichtwomodelsarethemodelsofDiffServ-AwardtrafficEngineering？（）
