OSPF behavior using different interface types.
| Interface Type | Uses DR/BDR? | Default Hello Interval |
Requires a neighbor Command? |
More than Two Hosts Allowed in the Subnet? |
| Broadcast | Yes | 10 | No | Yes |
| Point-to-point 1 | No | 10 | No | No |
| Nonbroadcast 2 (NBMA) | Yes | 30 | Yes | Yes | Point-to-multipoint | No | 30 | No | Yes |
| Point-to-multipoint nonbroadcast | No | 30 | Yes | Yes |
| Loopback | No | — | — | No |
1 Default on Frame Relay point-to-point subinterfaces.
2 Default on Frame Relay physical and multipoint subinterfaces.
Reference:
CCIE Routing and Switching Certification Guide 4th Edition