NBMA网络OSPF point-to-multipoint
1，无需采用全互联拓扑；常用于部分互联或星型拓扑。
2，无需静态指定邻居；点到多点模式将网络视为一系列的点到点邻居链路。
3，所有路由器接口位于同一子网内；
4，复制LSA分组，将发送给邻居表中的所有邻居。
5，默认Hello间隔时间为30秒，失效时间为120秒
配置：
FR：
FR(config)#no ip routing
FR(config)#frame-relay switching
FR(config)#int s0/0
FR(config-if)#no ip add
FR(config-if)#no sh
FR(config-if)#en fr
FR(config-if)#frame-relay intf-ty dce
FR(config-if)#clock rate 64000
FR(config-if)#frame-relay lmi-type cisco
FR(config-if)#frame-relay route 102 int s0/1 201
FR(config-if)#frame-relay route 103 int s0/2 301
FR(config-if)#exit
FR(config)#int s0/1
FR(config-if)#no sh
FR(config-if)#no ip add
FR(config-if)#en fr
FR(config-if)#frame-relay intf-type dce
FR(config-if)#clock rate 64000
FR(config-if)#frame-relay lmi-type cisco
FR(config-if)#frame-relay route 201 int s0/0 102
FR(config-if)#exit
FR(config)#int s0/2
FR(config-if)#no ip add
FR(config-if)#no sh
FR(config-if)#en fr
FR(config-if)#frame-relay intf-ty dce
FR(config-if)#clock rate 64000
FR(config-if)#frame-relay lmi-type cisco
FR(config-if)#frame-relay route 301 int s0/0 103
FR(config-if)#exit
R1：
R1(config)#int lo0
R1(config-if)#ip add 1.1.1.1 255.255.255.0
R1(config-if)#ip ospf net point-to-point
R1(config-if)#exit
R1(config)#int s0/0
R1(config-if)#no ip add
R1(config-if)#no sh
R1(config-if)#en fra
R1(config)#int s0/0.1 multipoint
R1(config-subif)#ip add 10.10.10.1 255.255.255.0
R1(config-subif)#frame-relay map ip 10.10.10.2 102 br
//静态指定frame-relay map ，关键字：broadcast
R1(config-subif)#frame-relay map ip 10.10.10.3 103 br
R1(config-subif)#ip ospf net point-to-multipoint
//指定OSPF类型为point-to-multipoint，默认为non-broadcast
R1(config)#router ospf 1
R1(config-router)#router-id 1.1.1.1
R1(config-router)#net 1.1.1.0 0.0.0.255 area 0
R1(config-router)#net 10.10.10.0 0.0.0.255 area 0
R1(config-router)#exit
R2：
R2(config)#int lo 0
R2(config-if)#ip add 2.2.2.2 255.255.255.0
R2(config-if)#ip ospf net point-to-point
R2(config-if)#exit
R2(config)#int s0/0
R2(config-if)#ip add 10.10.10.2 255.255.255.0
R2(config-if)#no sh
R2(config-if)#encapsulation frame-relay
R2(config-if)#frame-relay map ip 10.10.10.1 201 br
R2(config-if)#ip ospf net point-to-multipoint
R2(config)#router ospf 1
R2(config-router)#router-id 2.2.2.2
R2(config-router)#net 2.2.2.0 0.0.0.255 area 0
R2(config-router)#net 10.10.10.0 0.0.0.255 area 0
R2(config-router)#exit
R3：
R2(config)#int lo 0
R2(config-if)#ip add 3.3.3.3 255.255.255.0
R2(config-if)#ip ospf net point-to-point
R2(config-if)#exit
R3(config)#int s0/0
R3(config-if)#ip add 10.10.10.3 255.255.255.0
R3(config-if)#no sh
R3(config-if)#encapsulation frame-relay
R3(config-if)#frame-relay map ip 10.10.10.1 301 br
R3(config-if)#ip ospf net point-to-multipoint
R3(config)#router ospf 1
R3(config-router)#router-id 3.3.3.3
R3(config-router)#net 3.3.3.0 0.0.0.255 area 0
R3(config-router)#net 10.10.10.0 0.0.0.255 area 0
R3(config-router)#exit
查看OSPF的网络类型：
R1#sh ip ospf int s0/0.1
Serial0/0.1 is up, line protocol is up
Internet Address 10.10.10.1/24, Area 0
Process ID 1, Router ID 1.1.1.1, Network Type POINT_TO_MULTIPOINT, Cost: 64
Transmit Delay is 1 sec, State POINT_TO_MULTIPOINT,
Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5
oob-resync timeout 120
Hello due in 00:00:20
Supports Link-local Signaling (LLS)
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 4 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 3.3.3.3
Adjacent with neighbor 2.2.2.2
Suppress hello for 0 neighbor(s)
R1#sh ip ospf nei
Neighbor ID
Pri State Dead Time Address Interface
3.3.3.3 0 FULL/ - 00:01:35 10.10.10.3 Serial0/0.1
2.2.2.2 0 FULL/ - 00:01:46 10.10.10.2 Serial0/0.1
Network Type POINT_TO_MULTIPOINT，Hello ：30s，Dead：120s，不选举DR/BDR，自动建立邻居关系，无需手动指定。
R1#sh ip ro os
2.0.0.0/24 is subnetted, 1 subnets
O 2.2.2.0 [110/65] via 10.10.10.2, 00:00:05, Serial0/0.1
3.0.0.0/24 is subnetted, 1 subnets
O 3.3.3.0 [110/65] via 10.10.10.3, 00:00:05, Serial0/0.1
10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks
O 10.10.10.2/32 [110/64] via 10.10.10.2, 00:00:05, Serial0/0.1
O 10.10.10.3/32 [110/64] via 10.10.10.3, 00:00:05, Serial0/0.1