Explanation/Reference:
Explanation:
Before you troubleshoot any OSPF neighbor-related issues on an NBMA network, it is important to remember that an NBMA network can be configured in these modes of operation with the ipospf network command:
Point-to-Point
Point-to-Multipoint
Broadcast
NBMA
The Hello and Dead Intervals of each mode are described in this table:
Hello Interval Dead Interval
Network Type
(secs) (secs)
Point-to-Point 10 40
Point-to-Multipoint 30 120
Broadcast 10 40
Non-Broadcast 30 120
Reference: http://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/13693- 22.html