单项选择题
Router A is unable to reach Router B.Both routers are running ios version 12.0.After reviewing the command output and graphic,what is the most likely cause of the problem?（）
A. incorrect bandwidt h configuration B. incorrect LMI configuration C. incorrect map statement D. incorrect IP address
单项选择题 Which command enables IPv6 forwarding on a cisco router?（）
单项选择题 In the implementation of VLSM techniques on a network using a single Class C IP address,which subnet mask is the most efficient for point-to-point serial links?（）
单项选择题 Which IPv6 address is valid?（）
