Here is a simple network using OSPF. Router2 has got LoopBack0 with IP address 10.0.2.1 255.255.255.0. I add this network to OSPF:
Router(config-router)#net 10.0.2.0 0.0.0.255 area 0
When I dispaly routing table in Router2 - I see there 10.0.2.0/24 directly connected. But in Router3 routing table I see
10.0.0.0/32 is subnetted, 1 subnets
O 10.0.2.1 [110/65] via 10.0.0.2, 00:00:12, Serial0/0/0
Why there is prefix /32 ?