what is the advantage of policing opposite to shaping？

QoS機(jī)制中的分類，采用ip數(shù)據(jù)包中的哪個字段？

問一個怎么樣的屬性，能讓路由不通告給任何的peer？

The Frame Relay network in the diagram is not functioning properly.What is the cause of the problem?（） 

what is four ospf area type？

What is the three main step of using the QoS feature with MQC command line interface？

The following configuration line was added to router R1 Access-list 101 permit ip 10.25.30.00.0.0.255 any What is the effect of this access list configuration?（）

four switches， which one will be root switch.（no pic）.

Refer to the exhibit.The network administrator is in acampus building distant from Building B.WANRouter is hosting a newly installed WAN link on interface S0/0.The new link is not functioning and the administrator needs to determine if the correct cable has been attached to the S0/0 interface.How can the administrator accurately verify the correct cable type on S0/0 in the most efficient manner?（）

As a CCNA candidate,you must have a firm understanding of the IPv6 address structure.Refer to IPv6 address,could you tell me how many bits are included in each filed?（）