单项选择题
A. OSPF and mumber of hops and reliability
B. EIGRP and link cost
C. IS-IS and delay and reliability
D. RIPv2 and number of hops
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?（）
单项选择题 Which command encrypts all plaintext passwords?（）