A.physical layer

B.data link layer

C.application layer

D.presentation layer

E.session layer

F.transport layer

A.The packets sent by R1 to R2 are CSNP packets.

B.The packets sent by R1 to R2 are LSP packets.

C.The packets sent by R1 to R2 are Hello packets.

D.The packets sent by R1 to R2 are PSNP packets.

A.The G0/0/18 interface will continue to be in the Listening state andL earning status changes back and forth

B.The G0/0/17 interface will enter the Blocking state

C.G0/0/18 interface will enterDiscarding state

D.G0/0/17 interface and G0/0/18 interface will enterForwarding state

E.G0/0/17 interface and G0/0/18 interface will enterDiscarding state

A.The Hello packet must contain the interface ID of the sending interface

B.The LSR packet contains the complete LSA header information and is used to request to update the LSA

C.The LSACK message contains the LSA header information to confirm receipt of the LSU message

D.The Option field of Hello and DD packets is extended to 24 bits

A.Secure dynamic MAC address

B.Black hole MAC address

C.sticty MAC address

D.Secure static MAC address