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

Which statement describes the rule of split horizon?（）

While troubleshooting a network problem,a technician discovers that the current copy of the Cisco IOS is outdated and needs to be updated.Which of the following commands would the technician issue to replace the Cisco router IOS with the newer version?（）

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

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

Three switches are connected to one anther via trunk ports.Assuming the default switch configuration,which switch is elected as the root bridge for the spanning-tree instance of vlan 1?（）

Which name describes an IPV6 host-enable tunneling technique that uses IPV4 UDP,does not require dedicated gateway tunnels,and can pass through existing IPV4 NAT gateways?（）

Which address is the IPV6 all-RIP-routers muticast group address that is used by RIPng as the destaion address?（）

Which command encrypts all plaintext passwords?（）

Which command displays the CHAP authentication process as it occurs between two routers?（）