单项选择题

What is the effect of turning on all available downstream carrier tones in a DMT DSL transmissionsystems？（）

A.Downstream RS error correction effectiveness is reduced
B.The downstream line rate and throughput remains unchanged， but FEC efficiency is reduced
C.The upstream DSL bandwidth is reduced， since less carriers become available for upstream traffic
D.The downstream DSL bandwidth is increased

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热门试题

单项选择题WhichstatementisFALSEconcerningtheinterleavedepthvalue？（）

A.A higher interleave depth provides more protection from burst of noise on the HFC network
B.Higher interleave depth increase downstream latency
C.Lower interleave depth cause some packet loss on typical HFC networks
D.None ofthe above

多项选择题WhichtwoIOScommandsareequivalentsforputtingaCisco7500OC-12RPRinterfacecardintowrappedmode？（）

A.shutdown [a b]
B.srp shutdown [a b]
C.srp ips request manual-switched [a b]

单项选择题BGPbestrouteselectionprocessisbasedonpathattributes.（）

A.True
B.False

单项选择题HowmanycontentdefinitionsdoesCSGallow？（）

A.40
B.400
C.4000
D.40000

单项选择题WhatisthefunctionoftheAJBbitsonDS1usingExtendedSuperFrame（ESF）？（）

A.It is used for signaling on-hook and off-hook status
B.It carries CRC information for error detection
C.It is used for a control and performance information
D.It is used for a frame’s synchronization and alignment