单项选择题
Two Label-Switched Paths called LSP A and LSP B have been configured on a router. LSP A has been configured with a hold-priority of 3. There is insufficient reservable bandwidth along the path to accomodate both LSPs reservation requirements. Which setup priority must LSP B have to pre-empt LSP A and use its bandwidth?（）
A.2 B.3 C.4 D.7
多项选择题 Which three authentication options does IS-IS support?（）
多项选择题 In which two ways can you influence how downstream LSRs treat MPLS traffic?（）
多项选择题 Which three are well-known mandatory BGP attributes? （）
