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?（）

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.

单项选择题A network de sign shows area 1 with three internal routers, area 0 with four internal routers, and area 2 with five internal routers. Additionally, one ABR (ABR1) connects areas 0 and 1, plus a different ABR (ABR2) connects areas 0 and 2. How many Type 1 LSAs would b e listed in ABR2s LSDB?（）

A. 6
B. 7
C. 15
D. 12
E. None of the other answers is correct.

单项选择题A company has a Frame Relay WAN with one central - site router and 100 branch office routers. A partial mesh of PVCs exists: one PVC between the central site and each of t he 100 branch routers. All routers use point - to - point subinterfaces and one subnet per PVC. Which of the following is true about OSPF in this design?（）

A. The central site router has 100 fully adjacent neighborships with the 100 branches
B. The central  site router has neighborships with all branch routers, but fully adjacent neighbors with only two branches
C. The central site router has a neighborship with the Frame Relay switcH
D. None of the other answers is correct