What is the purpose of the cisco Vlan Trunking protocol?（）

The network administrator cannot to switch 1 over a telnet session,although the hosts attached to switch 1 can ping the interface Fa0/0 of the router.Given the information in the graphic and assuming that the router and switch2 are configured properly,which of the following commands should be issued on switch 1 to correct this problem?（）

While troubleshooting a network problem,a technician discovers that the current copy of the Cisco IOS is outdated and needs to be updated.Which of the following commands would the technician issue to replace the Cisco router IOS with the newer version?（）

Which Cisco IOS diagnostics command can disrupt the operation of a router under high-load conditions?（）

Which command is used to display the collection of OSPF link states?（）

At which layer of the OSI model dose PPP perform?（）

You have been asked to come up with a subnet mask that will allow all three web servers to be on the same network while providing the max number of subnets.Which network address and subnet mask meet this requirement?（）

Which statement describes the rule of split horizon?（）

Which device might be installed at a branch office to enable and manage an IPsec site-to-site VPN?（）

How are VTP advertisements delivered to switches across the network?（）