多项选择题
The Origin attribute describes the source of the BGP prefix. Which three are valid Origin codes?（） (Choose three.)
A.IGP B.BGP C.EGP D.Incomplete E.Anonymous
多项选择题 What are two uses of the AS Path attribute?（） (Choose two.)
多项选择题 Which three BGP attributes are always communicated in a BGP update packet? （）(Choose three.)
单项选择题 Which packet is sent in response to a BGP Open packet?（）
