单项选择题
Refer to the exhibit. Which of these is applied to the Bearer class？（）
A.WRED B.traffic shaping C.packet marking D.packet classification E.FIFO queuing within the class
Refer to the exhibit. Which switching feature is being ...
Refer to the exhibit. Which switching feature is being tested？（）
A.loop guard B.PortFast C.root guard D.BDPU guard
R1（AS1）------R2（AS2）-----R3（AS2）----R4（AS2） ，R1在AS1，R2，...
问答题
R1（AS1）------R2（AS2）-----R3（AS2）----R4（AS2） ，R1在AS1，R2，R3，R4在AS2，R1和R2建EBGP ， R2和R3 IBGP，R3和R4 IBGP，产生BGP路由从R1传给R2，问这条路有会不会在R4上出现，如果不会，怎么解决.
Refer to the exhibit. Voice traffic is marked "preceden...
Refer to the exhibit. Voice traffic is marked "precedence 5." How much bandwidth is allocated for voice traffic during periods of congestion？（）
A.a minimum of 48 kb/s B.a maximum of 48 kb/s C.a minimum of 48% of the available bandwidth D.a maximum of 48% of the available bandwidth
