Which of the following LSA types describes topology information that, when changed, requires a router in the same area to perform an SPF calculation?（）

单项选择题R1 is internal to area 1, and R2 is internal to area 2. Subnet 10.1.1.0 24 exists in area 2 as a connected subnet off R2. ABR ABR1 connects area 1 to backbone area 0, and ABR2 c onnects area 0 to area 2. Which of the following LSAs must R1 use when calculating R1s best route for 10.1.1.0 24?（）

A. R2's Type 1 LSA
B. Subnet 10.1.1.0/24's Type 2 LSA
C. ABR1's Type 1 LSA in area 0
D. Subnet 10.1.1.0/24's Type 3 LSA in Area 0
E.  Subnet 10.1.1.0/24's Type 3 LSA in Area 1

多项选择题Routers R1, R2, R3, and R4 connect to the same 10.10.10.0 24 LAN- based subnet. OSPF is fully working in the subnet. Later, R5, whose OSPF priority is higher than the other four routers, joins the subnet. Which of the following are true about the OSPF database exchange process over this subnet at this point?（）

A. R5 will send its DD, LSR, and LSU packets to the 224.0.0.5 all - DR - routers multicast address.
B. R5 will send its DD, LSR, and LSU pack ets to the 224.0.0.6 all - DR - routers multicast address.
C. The DR will inform R5 about LSAs by sending its DD, LSR, and LSU packets to the 224.0.0.6 all- SPF - routers multicast address.
D. The DR will inform R5 about LSAs by sending its DD, LSR, and LSU pa ckets to the 224.0.0.5 all- SPF - routers multicast address.

单项选择题Which of the following OSPF messages contains entire complete LSAs used during the database exchange process?（）

A. LSR
B. LSAck
C. LSU
D. DD
E. Hello

单项选择题A verification plan shows a network diagram with branch office Routers B1 through B100, plus two ABRs, ABR1, and ABR2, all in area 100. The branches connect to the ABRs using Frame Relay point - to - point subinterfaces. The verification plan lists the output of the show i p ospf database summary 10.100.0.0 command on a router B1, one of the branches. Which of the following is true regarding the output that could be listed for this command?（）

A. The output lists nothing unless 10.100.0.0 has been configured as a summary rou te using the area range command.
B. If 10.100.0.0 is a subnet in area 0, the output lists one Type 3 LSA, specifically the LSA with the lower metric when comparing ABR1's and ABR2's LSA for 10.100.0.0.
C. If 10.100.0.0 is a subnet in area 0, the output lists two Type 3 LSAs, one each created by BR1 and ABR2.
D. None, because the Type 3 LSAs would exist only in the ABR's LSDBs.

单项选择题A network planning diagram shows a large internetwork with many routers. The configurations show that OSPF has been enabled on all interfaces, I P addresses correctly configured, and OSPF workinG. For which of the following cases would you expect a router to create and flood a Type 2 LSA?（）

A. When OSPF is enabled on a LAN interface, and the router is the only router connected to the subnet.
B.  When OSPF is enabled on a point - to -point serial link, and that router has both the higher router ID and higher interface IP address on the link.
C. When OSPF is enabled on a Frame Relay point - to - point subinterface, has the lower RID and lower subinterfa ce IP address, and otherwise uses default OSPF configuration on the interface.
D. When OSPF is enabled on a working LAN interface on a router, and the router has been elected BDR.
E. None of the other answers is correct.