A.Protects signals when a ring switch fails
B.Protects signals when multiple span switches fail
C.Protects pre-emptible traffic from being dropped when a ring switch occurs
D.Protects signals against any combination of link failure in each ring

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

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

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

A.True
B.False

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

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

A.The modem is commanded by the CMTS to set to the specific channel
B.The modem uses the default value in the broadcom chipset
C.The modem tuner sets a level as defined by the DOCSIS specification
D.The modem tuner scans the downstream spectrum until digital QAM modulated signal is encountered

A.VTP
B.802.1 q
C.CDP
D.Skinny Station Protocol

A.Latency remains the same， but throughput is decreased.
B.Latency remains the same， but error correction effectives may also be reduced.
C.Latency is increased， but faster error correction occurs.
D.Fewer ATM PVCs can be provisioned on DSL line.