单项选择题
A.UniDirectional Loop Detection B.Unspecified Distribution Label Detection C.Unified Distribution Label Direction D.UniDirectional Link Detection
WhatwillsignificantlydegradeDSLperformance，regardlessof...
单项选择题What will significantly degrade DSL performance， regardless of DSL rate or line length？ （）
A.Microliters installed between a telephone and shared line B.POTS splitters at the subscriber’s end of the DSL line C.POTS splitters at the telco CO D.None of the other alternatives apply
ATMcarriesIPandPPPinformationwithATMcells.WhatATMadapta...
单项选择题ATM carries IP and PPP information with ATM cells. What ATM adaptation Layer is used when an ATMcell carries IP packets and PPP frames？（）
A.AAU2 B.AAL3 C.AAL4 D.AAL5
WhichtwoofthefollowingaredesignatedfieldsforMACtunnelin...
多项选择题Which two of the following are designated fields for MAC tunneling protocol（802.1 ah）？（）
A.Service Ethertype B.ISL C.PseudoLAN TAG D.802.1q VLAN TAG E.Control Word F.Tunnel Label
