What does UDLD stand for？（）

单项选择题WhatwillsignificantlydegradeDSLperformance，regardlessofDSLrateorlinelength？（）

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

单项选择题ATMcarriesIPandPPPinformationwithATMcells.WhatATMadaptationLayerisusedwhenanATMcellcarriesIPpacketsandPPPframes？（）

A.AAU2
B.AAL3
C.AAL4
D.AAL5

多项选择题WhichtwoofthefollowingaredesignatedfieldsforMACtunnelingprotocol（802.1ah）？（）

A.Service Ethertype
B.ISL
C.PseudoLAN TAG
D.802.1q VLAN TAG
E.Control Word
F.Tunnel Label

单项选择题ASuccessoris（）.

A.A neighbor that has met the feasibility condition
B.A neighbor that has met the feasibility condition and has the lowest cost path towards the destination
C.Any neighbor that is in the path towards the destination.
D.Any neighbor that is in the path towards the destination and whose reported distance equals thefeasible distance

单项选择题RoutesredistributedintoanOSPFASBRarewhichLSAtype？（）

A.LSA type 1
B.LSA type 2
C.LSA type 3
D.LSA type 4
E.LSA type 5
F.LSA type 6