单项选择题
A. anycast frames
B. multicast frames
C. broadcast frames
D. unicast frames
单项选择题 Which pairing reflects a correct protocol-and-metric relationship?（）
单项选择题 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?（）
单项选择题 Which Cisco IOS diagnostics command can disrupt the operation of a router under high-load conditions?（）