A.The route learned through BGP, the Origin attribute is EGP.

B.Origin attribute three worthy priority order is EGP>IGP>INCOMOLETE

C.Injecting BGP routes through the network command, the Origin attribute is IGP.

D.Injecting BGP routes through the import command, the Origin attribute is Incomplete.

A.Update

B.Open

C.Hello

D.Keepalive

A.Interne

B.Advertise

C.NO-EXPORT(OxFFFFFFOI)

D.NO-ADVERTISE(OxFFFFFF02)

A.Level-1 router

B.Level-12 router

C.Level-3 router

D.Level-2 router

A.The router will query specific groups.

B.The router maintains a timeout timer for each group membership. If the receiver receives a host, it refreshes the timer. If the timer times out, the router deletes the membership of the group.

C.The router does not delete a group membership unless a corresponding leave message is received.

D.The router periodically sends a Query message. After receiving the Query message, the receiver host reports the Report message.