Whiletroubleshootinganetwork，youneedtoverifytheliveness……

单项选择题Whichmechanismcanyouusetoachievesub-secondfailoverforlinkfailuredetectionwhenaswitchedEthernetmediaisusedandlossofsignalisnotsupportedbythelinkprovider？（）

A.OSPF standard hellos
B.Cisco Discovery Protocol link detection
C.Bidirectional Forwarding Detection
D.Fast Link Pulse
E.autonegotiation

单项选择题Refer to the exhibit. R2 and R3 are routers connected using Ethernet services from a service provider and can receive pings from each other. OSPF is configured as the routing protocol but adjacency is not happening. According to the output of the show commands in the exhibit, what could be the most likely cause of the problem?（）

A.Ethernet interfaces were configured as point-to-point.
B.Process IDs are not matching.
C.Configured bandwidths do not match on both interfaces.
D.Broadcasts and multicast are not being propagated over the Ethernet services.
E.OSPF cost does not match on both interfaces.

问答题itisbelongafamilyofiproutingprotocols，eachrouterhaveapartialmapofnetwork，whatistheroutingprotocol？

问答题什么环境下需要用组播？

单项选择题Refer to the exhibit. You are setting up a 2-gigabit EtherChannel. Following IEEE standards, the exhibit shows your configuration in a local switch1. However, EtherChannel is not coming up. Which one of these statements could be a possible reason?（）

A.EtherChannel is only available in Cisco equipment.
B.The customer side is supposed to be running PAgP， which is a Cisco standard.
C.PAgP is not an IEEE standard. VRRP should be used.
D.The configuration on switch1 needs to be modified to use LACP.