Persistent vs Intermittent Attacks
"Researchers at North Carolina State University examined
two Wi-Fi attack types -- persistent attacks, in which the attack persists
non-stop until it can be identified and disabled, and intermittent attacks,
which block access on a periodic basis, making them harder to identify and stop.
They were able to measure the impact of both attacks."
They concluded that all attacks cannot be prevented and that a sensible policy would be to target those that would cause the most damage, which often would be the persistent attacks.
for a release on this study, check this link.