If all OSPF routers in a single area are configured with the same priority value,what value dose a router use for the ODPF router ID in the absence of a loopback interface?（）

A router receives information about network 192.168.10.0/24 from multiple sources.What will the router consider the most reliable information about the path to that network?（）

Which IPsec security protocol should be used when confidentiality is required?（）

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

While troubleshooting a network problem,a technician discovers that the current copy of the Cisco IOS is outdated and needs to be updated.Which of the following commands would the technician issue to replace the Cisco router IOS with the newer version?（）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 command can help to determine the timing of various debug events,relative to each other,when you are debugging a complicated router issue?（）

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?（）

What is the default administrative distance of OSPF?（）

Which protocol reduces administrative overhead in a switched network by allowing the configuration of a new VLAN to be distributed to all the switches in a domain?（）

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