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

QoS Mechanisms：?jiǎn)栐诓渴餛oS中要用的3個(gè)mechanisms是什么？

what is the disadvantage of policing？

What is the next state of initial in spanning-tree protocol？

SPT初始狀態(tài)之后的一個(gè)狀態(tài)是什么？

A network administrator is troubleshooting the OSPF configuration of routers R1 and R2.The routers cannot establish an adjacency relationship on their common Ethernet link.The graphic shows the output of the show ip ospf interface e0 command for routers R1 and R2.Based on the information in the graphic,what is the cause of this problem?（）

What is method list for configure aaa？

一堆交換機(jī)一個(gè)server、一個(gè)transpare，問(wèn)配置prune在哪里配置？

Refer to the exhibit.What is the meaning of the term dynamic as displayed in the output of the show frame-relay map command shown？（）

What field in IP packet is used for classification by QOS？