A.Configure OSPF between trigger router and black hole routes
B.Configure all edge routers with static （reserved） host route to Null0
C.Configure BGP beteen trigger and black hole routers
D.Configure on trigger router to advertise victim host route with commumity
E.Activate black hole by redistributing route for victim into BGP with next-hop set to the static（reserved）host route configured on edge routers

A.CoPP protects against IP spoofing；Racl protects against DoS attacks.
B.CoPP can not use named access lists；Racl can use named access lists
C.CoPP applies to a dedicated control plane interface；Racl applies to all interfaces.
D.CoPP needs a AAA server，Racl does not need a AAA server
E.CoPP supports rate limits；Racl does not support rate limits

A.OSPF
B.ISIS
C.BGP
D.RSVP
E.PIM

A.IS-Type
B.Overload （LSPDBOL）
C.Pseudonode （PN）
D.Attached （ATT）
E.Fragment （Frag-Nr）
F.Partition （P）

A.bgp
B.mpls_idp
C.sysmgr
D.wdsysmon
E.gsp

A.normal
B.select
C.random
D.discard
E.full

A.IP Precedence 2
B.IP Precedence 3
C.IP Precedence 4
D.IP Precedence 5
E.IP Precedence 6
F.IP Precedence 7

A.Level-1（L1） routers use default routes announced by Level-2（L2） routers in Level-1（L1） domain
B.Level-1 routers use default routes installed based on ATT bit （Attach Bit） in announcements from Level-1-2（L1/L2） router
C.Level-1 routers use specific routes， for other Level-1 domain， announced by Level-1-2（L1/L2） by route-leaking feature of Cisco IOS
D.Level-1 routers use specific routes， for other Level-1 domain， announced by Level-2（L2） by route-leaking feature of Cisco IOS

A.By default，Netflow records bidirectional IP traffic flow.
B.Netflow answers questions regarding IP traffic：who，what，where，when，and how
C.Netflow accounts for both transit traffic and traffic destined for the router.
D.Netflow returns the subinterface information in the flow records.

A.PW capabilities list
B.Message type
C.Assigned control connection ID
D.PW type
E.Remote session ID
F.Hostname