An architecture that utilizes PPPoE deals with IP address allocation by what type ofnegotiation？（）

A.The dspload screen is for all trunks； the dsptrkutl screen is for one trunk
B.The dspload screen shows the expected traffic； the dsptrkutl screen shows actual traffice
C.The information on the dspload screen never changes； the dsptrkutl screen is dynamic
D.The dspload screen shows historical information； the dsptrkutl screen shows current information

A.Set top box
B.Diplex filter
C.Local head end
D.Fiber node

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