OSPF Network Types

Here is a quick summary of OSPF Network types:

Network Type	LSA Flooding	DR/BDR Election	Timers	Neighbor Statement	Modify Next-hop	Default
Broadcast	Multicast	Yes	10/40	No	No	Ethernet
NBMA	Unicast	Yes	30/120	Yes	No	Default on Frame-Relay Physical and Point-to-Multipoint
Point-to-Point	Multicast	No	10/40	No	No	Default on Frame-Relay Point-to-Point sub-interface
Point-to-Multipoint	Multicast	No	30/120	No	Yes	Ideal for NBMA
Point-to-Multipoint Non-broadcast	Unicast	No	30/120	Yes	Yes
Loopback		No	30/120	No	No