This field specifies the OSPF hello interval in seconds within a link profile, ranging from 1 to 255 and defaulting to 10. An admin shortens this to make OSPF detect a dead neighbor faster at the cost of more frequent hello traffic, or lengthens it to reduce protocol overhead on a slow or congested link. Both ends of an OSPF adjacency must agree on this interval, so mismatched hello intervals between two profiles applied to peer interfaces is a common cause of a stalled adjacency.