Which statement is true, as relates to classful or classless routing?（）

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?（）

After the show ip route command has been entered,the follwing routes are displayed.Which route will not be entered into the routing table of a neighboring router?（）

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 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?（）

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?（）

A network administrator needs to configure a serial link between the main office and a remote location.The router at the remote office is a non-cisco router. How should the network administrator configure the serial interface of the main office router to make the connection?（）

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

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

Which encapsulation type is a Frame Relay encapsulation type that is supported by Cisco routers?（）