单项选择题
On which destination port in the Layer 4 header does BGP listen?（）
A. UDP port 169 B. TCP port 169 C. UDP port 179 D. TCP port 179
单项选择题 Which CLI command displays the metrics associated with each advertised route?（）
单项选择题 Which CLI command displays the IS-IS level used by each interface?（）
单项选择题 Which CLI command shows if the router has formed any IS-IS adjacencies?（）
